From 9a6337e4933728d7aa3ade210ce9aa36530a0369 Mon Sep 17 00:00:00 2001
From: buenosairesam <mariano@gotadeinfo.com>
Date: Mon, 10 Aug 2026 05:36:32 -0300
Subject: [PATCH] updates 33.1 84

---
 .gitignore                                    |   4 +
 build.py                                      | 220 ++++++++
 docs/data/en/export.md                        | 124 +++++
 docs/data/en/station-cabinets.md              | 107 ++++
 docs/data/en/station-datagen.md               | 103 +++-
 docs/data/en/station-modelgen.md              | 117 +++--
 docs/data/en/station-shuntgen.md              | 129 +++++
 docs/data/topics.json                         |   3 +
 soleprint/artery/index.html                   | 124 ++---
 .../artery/shunts/mercadopago/api/routes.py   |  11 +-
 .../artery/shunts/mercadopago/datagen.py      | 182 +++++++
 soleprint/artery/shunts/mercadopago/main.py   |   6 +-
 soleprint/atlas/index.html                    |  30 +-
 soleprint/common/theme/theme.js               | 118 +++++
 soleprint/common/theme/themes/mcrn.css        | 110 ++++
 soleprint/common/theme/themes/soleprint.css   | 113 ++++
 soleprint/common/theme/tokens.css             | 217 ++++++++
 soleprint/index.html                          |  60 +--
 soleprint/requirements.txt                    |   6 +
 soleprint/run.py                              | 156 +++++-
 soleprint/station/cabinets/README.md          |  91 ++++
 .../station/cabinets/airflow/cabinet.json     |  22 +
 .../station/cabinets/airflow/service.yml      |  37 ++
 .../station/cabinets/postgres/cabinet.json    |  20 +
 .../station/cabinets/postgres/service.yml     |  24 +
 soleprint/station/cabinets/redis/cabinet.json |  17 +
 soleprint/station/cabinets/redis/service.yml  |  14 +
 soleprint/station/index.html                  |  70 ++-
 .../tools/datagen/templates/index.html        |  19 +-
 .../tools/graphgen/templates/index.html       |  18 +-
 soleprint/station/tools/modelgen/__main__.py  | 152 +++++-
 .../tools/modelgen/generator/__init__.py      |   4 +
 .../tools/modelgen/generator/datagen.py       | 399 ++++++++++++++
 .../tools/modelgen/generator/jsonschema.py    |   3 +-
 .../tools/modelgen/generator/protobuf.py      |   5 +-
 .../station/tools/modelgen/loader/__init__.py |  14 +-
 .../tools/modelgen/loader/extract/__init__.py |  20 +-
 .../tools/modelgen/loader/extract/openapi.py  | 440 ++++++++++++++++
 .../tools/modelgen/loader/extract/tabular.py  | 450 ++++++++++++++++
 .../station/tools/modelgen/loader/schema.py   |  51 +-
 .../station/tools/modelgen/tests/__init__.py  |  18 +
 .../tools/modelgen/tests/test_extractors.py   | 406 +++++++++++++++
 soleprint/station/tools/modelgen/types.py     |  10 +
 soleprint/station/tools/shuntgen/README.md    | 127 +++++
 soleprint/station/tools/shuntgen/__init__.py  |  29 ++
 soleprint/station/tools/shuntgen/__main__.py  | 239 +++++++++
 soleprint/station/tools/shuntgen/api.py       | 354 +++++++++++++
 soleprint/station/tools/shuntgen/emit.py      | 462 +++++++++++++++++
 .../tools/shuntgen/fixtures/petstore.yaml     | 147 ++++++
 .../shuntgen/fixtures/sheets/customers.csv    |   6 +
 .../shuntgen/fixtures/sheets/invoices.csv     |   7 +
 .../shuntgen/fixtures/sheets/line_items.ods   | Bin 0 -> 1076 bytes
 soleprint/station/tools/shuntgen/runtime.py   | 489 ++++++++++++++++++
 .../tools/shuntgen/templates/index.html       | 294 +++++++++++
 .../tools/shuntgen/templates/shunt_ui.html    | 242 +++++++++
 55 files changed, 6387 insertions(+), 253 deletions(-)
 create mode 100644 docs/data/en/export.md
 create mode 100644 docs/data/en/station-cabinets.md
 create mode 100644 docs/data/en/station-shuntgen.md
 create mode 100644 soleprint/artery/shunts/mercadopago/datagen.py
 create mode 100644 soleprint/common/theme/theme.js
 create mode 100644 soleprint/common/theme/themes/mcrn.css
 create mode 100644 soleprint/common/theme/themes/soleprint.css
 create mode 100644 soleprint/common/theme/tokens.css
 create mode 100644 soleprint/station/cabinets/README.md
 create mode 100644 soleprint/station/cabinets/airflow/cabinet.json
 create mode 100644 soleprint/station/cabinets/airflow/service.yml
 create mode 100644 soleprint/station/cabinets/postgres/cabinet.json
 create mode 100644 soleprint/station/cabinets/postgres/service.yml
 create mode 100644 soleprint/station/cabinets/redis/cabinet.json
 create mode 100644 soleprint/station/cabinets/redis/service.yml
 create mode 100644 soleprint/station/tools/modelgen/generator/datagen.py
 create mode 100644 soleprint/station/tools/modelgen/loader/extract/openapi.py
 create mode 100644 soleprint/station/tools/modelgen/loader/extract/tabular.py
 create mode 100644 soleprint/station/tools/modelgen/tests/__init__.py
 create mode 100644 soleprint/station/tools/modelgen/tests/test_extractors.py
 create mode 100644 soleprint/station/tools/shuntgen/README.md
 create mode 100644 soleprint/station/tools/shuntgen/__init__.py
 create mode 100644 soleprint/station/tools/shuntgen/__main__.py
 create mode 100644 soleprint/station/tools/shuntgen/api.py
 create mode 100644 soleprint/station/tools/shuntgen/emit.py
 create mode 100644 soleprint/station/tools/shuntgen/fixtures/petstore.yaml
 create mode 100644 soleprint/station/tools/shuntgen/fixtures/sheets/customers.csv
 create mode 100644 soleprint/station/tools/shuntgen/fixtures/sheets/invoices.csv
 create mode 100644 soleprint/station/tools/shuntgen/fixtures/sheets/line_items.ods
 create mode 100644 soleprint/station/tools/shuntgen/runtime.py
 create mode 100644 soleprint/station/tools/shuntgen/templates/index.html
 create mode 100644 soleprint/station/tools/shuntgen/templates/shunt_ui.html

diff --git a/.gitignore b/.gitignore
index 465bd67..986c43b 100644
--- a/.gitignore
+++ b/.gitignore
@@ -19,6 +19,10 @@ dist/
 # Generated runnable instance (entirely gitignored - regenerate with build.py)
 gen/
 
+# Specs and sheets uploaded through shuntgen's UI. Inputs someone dropped in a
+# browser, not source — and often a client's real data.
+soleprint/station/tools/shuntgen/uploads/
+
 # Room configurations (separate repo - contains credentials and room-specific data)
 # Keep cfg/standalone/ and cfg/sample/ as templates, ignore actual rooms
 cfg/amar/
diff --git a/build.py b/build.py
index d73dd8e..cacdd8a 100644
--- a/build.py
+++ b/build.py
@@ -317,6 +317,221 @@ def copy_cfg(output_dir: Path, room: str):
                 copy_path(item, output_dir / item.name)
 
 
+def load_cabinets(room: str) -> list[dict]:
+    """The dependency containers a room asked for, in the order it listed them.
+
+    Read from cfg/<room>/data/cabinets.json — the same shape and the same place
+    as its sibling data/*.json files, so nothing new has to know about it.
+    Entries are {"name": "postgres"} and may carry an "env" override.
+    """
+    path = SPR_ROOT / "cfg" / room / "data" / "cabinets.json"
+    if not path.exists():
+        return []
+    try:
+        entries = json.loads(path.read_text())
+    except ValueError as e:
+        log.warning(f"  cabinets.json is not valid JSON, ignoring: {e}")
+        return []
+
+    out = []
+    for entry in entries if isinstance(entries, list) else []:
+        if isinstance(entry, str):
+            entry = {"name": entry}
+        if isinstance(entry, dict) and entry.get("name"):
+            out.append(entry)
+    return out
+
+
+def resolve_cabinets(requested: list[dict]) -> list[dict]:
+    """Expand each request into its definition, pulling in what it depends on.
+
+    Airflow without postgres is a container that exits on boot, so a cabinet's
+    depends_on is added for you rather than left as something to remember.
+    """
+    cabinets_dir = SPR_ROOT / "soleprint" / "station" / "cabinets"
+    resolved: dict[str, dict] = {}
+
+    def add(name: str, overrides: dict) -> None:
+        if name in resolved:
+            # Already pulled in as somebody's dependency. The room asking for it
+            # by name is the more specific statement, so its env still applies —
+            # otherwise declaring airflow before postgres would silently drop
+            # postgres's settings.
+            if overrides.get("env"):
+                resolved[name]["env"] = {
+                    **resolved[name].get("env", {}),
+                    **overrides["env"],
+                }
+            return
+        definition_path = cabinets_dir / name / "cabinet.json"
+        if not definition_path.exists():
+            available = sorted(
+                p.name for p in cabinets_dir.iterdir() if p.is_dir()
+            ) if cabinets_dir.exists() else []
+            log.warning(f"  no such cabinet: {name} (available: {', '.join(available) or 'none'})")
+            return
+        try:
+            definition = json.loads(definition_path.read_text())
+        except ValueError as e:
+            log.warning(f"  cabinet {name} has invalid cabinet.json: {e}")
+            return
+
+        # Mark it claimed before recursing, so a dependency cycle terminates.
+        resolved[name] = definition
+        for dependency in definition.get("depends_on", []) or []:
+            add(dependency, {})
+
+        definition["env"] = {**definition.get("env", {}), **overrides.get("env", {})}
+
+    for entry in requested:
+        add(entry["name"], entry)
+
+    # Dependencies first, so compose reads in the order things start.
+    ordered: list[dict] = []
+    seen: set[str] = set()
+
+    def emit(name: str) -> None:
+        if name in seen or name not in resolved:
+            return
+        seen.add(name)
+        for dependency in resolved[name].get("depends_on", []) or []:
+            emit(dependency)
+        ordered.append(resolved[name])
+
+    for name in resolved:
+        emit(name)
+    return ordered
+
+
+def compose_cabinets(output_dir: Path, room: str):
+    """Merge the room's cabinets into its docker-compose.yml and .env.example.
+
+    This is the compile step for dependencies: a room declares postgres, and the
+    built instance comes out with postgres in its compose file rather than with
+    instructions for adding it.
+    """
+    requested = load_cabinets(room)
+    if not requested:
+        return
+
+    try:
+        import yaml
+    except ImportError:
+        log.warning(
+            "  cabinets need PyYAML to merge into docker-compose.yml "
+            "(pip install pyyaml) — skipping"
+        )
+        return
+
+    cabinets = resolve_cabinets(requested)
+    if not cabinets:
+        return
+
+    compose_path = output_dir / "docker-compose.yml"
+    if not compose_path.exists():
+        log.warning(
+            f"  no docker-compose.yml in {output_dir.name}, "
+            f"so there is nothing to merge {len(cabinets)} cabinet(s) into"
+        )
+        return
+
+    original = compose_path.read_text()
+    # A YAML round-trip drops every comment, and the room's compose file leads
+    # with the one that says how to run it. Keep the header block; the rest is
+    # generated anyway.
+    header = []
+    for line in original.splitlines():
+        if line.startswith("#") or not line.strip():
+            header.append(line)
+        else:
+            break
+    while header and not header[-1].strip():
+        header.pop()
+
+    compose = yaml.safe_load(original) or {}
+    services = compose.setdefault("services", {})
+    volumes = compose.setdefault("volumes", {}) or {}
+    cabinets_dir = SPR_ROOT / "soleprint" / "station" / "cabinets"
+
+    added, skipped = [], []
+    for cabinet in cabinets:
+        name = cabinet["name"]
+        service_name = cabinet.get("service", name)
+
+        # The room's own compose file is the authority. A room that already
+        # declares `db` has arranged it deliberately, and silently replacing it
+        # would be the worst possible outcome of switching a cabinet on.
+        if service_name in services:
+            skipped.append(service_name)
+            continue
+
+        fragment_path = cabinets_dir / name / "service.yml"
+        if not fragment_path.exists():
+            log.warning(f"  cabinet {name} has no service.yml")
+            continue
+
+        fragment = yaml.safe_load(fragment_path.read_text()) or {}
+        for key, value in fragment.items():
+            if key in services:
+                skipped.append(key)
+                continue
+            services[key] = value
+            added.append(key)
+
+        for volume in cabinet.get("volumes", []) or []:
+            volumes.setdefault(volume, None)
+
+    if volumes:
+        compose["volumes"] = volumes
+
+    rendered = yaml.safe_dump(compose, sort_keys=False, default_flow_style=False)
+    banner = f"# Cabinets merged in by build.py: {', '.join(c['name'] for c in cabinets)}.\n"
+    preamble = ("\n".join(header) + "\n" + banner + "\n") if header else banner + "\n"
+    compose_path.write_text(preamble + rendered)
+
+    if added:
+        log.info(f"  cabinets: {', '.join(added)}")
+    if skipped:
+        log.info(f"  cabinets already declared by the room, left alone: {', '.join(skipped)}")
+
+    _append_cabinet_env(output_dir, cabinets)
+
+
+def _append_cabinet_env(output_dir: Path, cabinets: list[dict]):
+    """Add each cabinet's settings to .env.example, without touching .env."""
+    example = output_dir / ".env.example"
+    existing = example.read_text() if example.exists() else ""
+    # Match whole settings, not substrings: `POSTGRES_DB=` appears inside
+    # `MY_POSTGRES_DB=`, and a substring test would decide the setting was
+    # already there and skip it.
+    declared = {
+        line.split("=", 1)[0].strip()
+        for line in existing.splitlines()
+        if "=" in line and not line.lstrip().startswith("#")
+    }
+
+    lines = []
+    for cabinet in cabinets:
+        env = cabinet.get("env", {})
+        if not env:
+            continue
+        block = [f"\n# ── {cabinet.get('title', cabinet['name'])} (cabinet) ──"]
+        for note in cabinet.get("notes", []) or []:
+            block.append(f"# {note}")
+        wrote = False
+        for key, value in env.items():
+            if key in declared:
+                continue
+            block.append(f"{key}={value}")
+            declared.add(key)
+            wrote = True
+        if wrote:
+            lines.extend(block)
+
+    if lines:
+        example.write_text(existing.rstrip("\n") + "\n" + "\n".join(lines) + "\n")
+
+
 def build_soleprint(output_dir: Path, room: str):
     """Build soleprint folder with core + room config merged."""
     soleprint = SPR_ROOT / "soleprint"
@@ -348,6 +563,11 @@ def build_soleprint(output_dir: Path, room: str):
     # Room config (includes merging room-specific artery/atlas/station)
     copy_cfg(output_dir, room)
 
+    # Dependency containers the room asked for, merged into its compose file.
+    # After copy_cfg, because the compose file being merged into is the room's.
+    log.info("Composing cabinets...")
+    compose_cabinets(output_dir, room)
+
     # Generate models
     log.info("Generating models...")
     if not generate_models(output_dir, room):
diff --git a/docs/data/en/export.md b/docs/data/en/export.md
new file mode 100644
index 0000000..9b06ac5
--- /dev/null
+++ b/docs/data/en/export.md
@@ -0,0 +1,124 @@
+# Export / Compile
+
+Soleprint's source tree is not what runs. `build.py` compiles the framework plus
+a room's configuration into a self-contained instance under `gen/<room>/`, and
+that directory is what a container boots, what `deploy.sh` rsyncs, and what the
+cluster manifests point at.
+
+Everything below is a `make` target, and every target is one script in `ctrl/`.
+The logic lives in the scripts, never in the Makefile.
+
+```bash
+make build            # cfg/standalone -> gen/standalone
+make build sample     # cfg/sample     -> gen/sample
+make start            # run it
+```
+
+## The targets
+
+| Command | Runs | Does |
+| --- | --- | --- |
+| `make build [<room>\|all\|models]` | `ctrl/build.sh` | compile a room into `gen/` |
+| `make start [<room>] [-d]` | `ctrl/start.sh` | run a built room's compose stack |
+| `make stop [<room>]` | `ctrl/stop.sh` | stop it |
+| `make cluster [up\|down\|status]` | `ctrl/cluster.sh` | the shared kind cluster |
+| `make component [list\|publish\|sync\|watch\|diff]` | `ctrl/spr.py` | publish a distributable component |
+| `make deploy` | `ctrl/deploy.sh` | rsync `gen/standalone` to the server and restart |
+
+Bare words pass straight through, so `make build sample` becomes
+`ctrl/build.sh sample`. Anything starting with a dash would be eaten by make
+itself, so those go through `ARGS`:
+
+```bash
+make deploy    ARGS="--build"
+make component ARGS="publish soleprint-ui /tmp/out --dist"
+```
+
+## What a build does
+
+`python build.py --cfg <room>` runs these in order:
+
+1. **Clean** `gen/<room>/`. A build is not incremental — a stale file left
+   behind is worse than a slow build.
+2. **Copy the framework.** `main.py`, `run.py`, `index.html`, `Dockerfile`,
+   `requirements.txt`, `dataloader/`, `common/`, and the three systems
+   (`artery/`, `atlas/`, `station/`).
+3. **Merge the room** (`copy_cfg`). `cfg/<room>/config.json` lands in `cfg/`,
+   `data/*.json` in `data/`, and anything under `cfg/<room>/soleprint/artery|atlas|station/`
+   is merged *over* the framework copy — which is how a room adds its own vein,
+   shunt, tool or generator without forking the tree.
+4. **Compose cabinets.** The dependency containers the room declared in
+   `data/cabinets.json` are merged into its `docker-compose.yml`. See
+   [Cabinets](#station-cabinets).
+5. **Generate models.** modelgen reads the room's `config.json` and writes
+   `models/pydantic/__init__.py`.
+6. **Render k8s** (optional). When the room's config enables it,
+   `soleprint/ctrl/k8s/` writes manifests and lifecycle scripts.
+
+## What comes out
+
+A standalone room is a flat instance:
+
+```
+gen/standalone/
+  run.py  main.py  Dockerfile  docker-compose.yml
+  artery/  atlas/  station/  common/
+  cfg/config.json
+  data/*.json
+  models/pydantic/
+```
+
+A **managed** room — one that wraps an existing application — is three folders
+instead, because soleprint sits beside the app rather than containing it:
+
+```
+gen/<room>/
+  <app>/        the application's repos, plus its ctrl scripts
+  link/         bridge code between the two
+  soleprint/    the instance, exactly as above
+```
+
+`build.py` picks between them on whether the room's `config.json` has a
+`managed` block. `gen/` is gitignored in full: it is an artifact, and the way to
+change it is to change `cfg/<room>/` and rebuild.
+
+## Distributing components
+
+Rooms are compiled; *components* are published. `registry.json` lists what can
+be shipped out of this repo on its own:
+
+```bash
+make component                                            # list
+make component ARGS="publish soleprint-ui /tmp/out --dist"
+make component ARGS="watch soleprint-ui ../unt/ui/framework"
+```
+
+`--dist` copies only the built bundle — `dist/**` plus `package.json`,
+`README.md` and `LICENSE` — rather than the source. It refuses to publish an
+empty `dist/`, because a component whose bundle was never built is the failure
+that shows up later as a container that starts and renders nothing:
+
+```
+no build at soleprint/common/ui
+build it first: cd soleprint/common/ui && pnpm build
+```
+
+Each publish leaves a `.spr` stamp in the destination recording name, version,
+type, source and mode, so a copy can say where it came from.
+
+## Deploying
+
+```bash
+make deploy ARGS="--build"      # rebuild, sync, restart
+make deploy ARGS="--sync-only"  # sync, leave it running
+```
+
+`deploy.sh` rsyncs `gen/standalone/` and runs `docker compose up -d --build` on
+the far side. `.env` is excluded, so server secrets stay on the server.
+
+## Running without building
+
+`python run.py` from `soleprint/` serves every subsystem on one port (12000 by
+default) straight from the source tree. It is for developing the framework
+itself; a room's `cfg/config.json` does not exist there, so the landing pages
+fall back to their defaults. Rooms use docker.
diff --git a/docs/data/en/station-cabinets.md b/docs/data/en/station-cabinets.md
new file mode 100644
index 0000000..d812010
--- /dev/null
+++ b/docs/data/en/station-cabinets.md
@@ -0,0 +1,107 @@
+# Cabinets
+
+A cabinet is a **dependency container** a room can switch on: postgres, redis,
+airflow. The vocabulary already had the word — `execution.container` in every
+room's `config.json` is *"Cabinet — tool container"* — and until now nothing
+stood behind it.
+
+The problem it solves: a generated artifact knows what it needs and had no way
+to say so. A shunt built from a client's spreadsheets holds its rows in memory
+happily, but the moment you want them to survive a restart you need postgres,
+and wiring postgres in meant hand-editing a room's `docker-compose.yml` and then
+hand-editing the cluster too. A cabinet is that declaration, made once and read
+by both paths.
+
+## Switching one on
+
+Add `cfg/<room>/data/cabinets.json`, the same shape as its sibling `data/*.json`
+files:
+
+```json
+[
+  { "name": "postgres" },
+  { "name": "redis" },
+  { "name": "airflow", "env": { "AIRFLOW_ADMIN_PASSWORD": "change-me" } }
+]
+```
+
+Then build. The compose merge is a step in [Export / Compile](#export):
+
+```bash
+python build.py --cfg sample
+cd gen/sample && docker compose up -d
+```
+
+`build.py` merges each cabinet's compose fragment into the room's
+`docker-compose.yml`, declares its named volumes, and appends its settings to
+`.env.example` — never to `.env`.
+
+**A service the room already declares wins.** `cfg/amar/docker-compose.yml`
+ships its own `db`; switching the postgres cabinet on will not replace it. The
+build says so when it skips one:
+
+```
+Composing cabinets...
+  cabinets: redis, airflow
+  cabinets already declared by the room, left alone: postgres
+```
+
+Dependencies come along automatically. Airflow without a metadata database is a
+container that exits on boot, so asking for `airflow` brings `postgres` and
+`redis` with it, ordered so compose reads them before the thing that needs them.
+
+## On a cluster
+
+Every cabinet names a `rig_addon`. Where a room runs on kind rather than
+compose, the same dependency installs as a rig addon of that name:
+
+```bash
+cd rig
+PROFILE=data make cluster up
+PROFILE=data make addons install
+
+kubectl -n data port-forward svc/postgres 5432:5432
+kubectl -n data port-forward svc/airflow  8080:8080
+```
+
+The two paths are deliberately separate — compose for a laptop, manifests for a
+cluster — and `rig_addon` is the thread between them, so the room declares the
+dependency once either way. The addons generate their own passwords on first
+install and keep them across re-runs, so re-running never rotates a credential
+out from under something already connected.
+
+## What ships
+
+| Cabinet | Image | Notes |
+| --- | --- | --- |
+| `postgres` | `postgres:16-alpine` | healthcheck wired, so `depends_on: service_healthy` works |
+| `redis` | `redis:7-alpine` | cache, and the broker for anything queue-shaped |
+| `airflow` | `apache/airflow:2.10.4` | one container on `standalone`; needs postgres and redis |
+
+## Writing one
+
+```
+soleprint/station/cabinets/<name>/
+  cabinet.json    what it is, what it needs, what it exports
+  service.yml     the compose service, verbatim
+```
+
+`cabinet.json`:
+
+| Key | Purpose |
+| --- | --- |
+| `name` | must match the directory |
+| `title`, `description` | shown on the station index |
+| `service` | the key to merge under in `services:` (defaults to `name`) |
+| `env` | settings and defaults, written to `.env.example` |
+| `volumes` | named volumes to declare at the top level |
+| `depends_on` | other cabinets that must come with it |
+| `rig_addon` | the matching `rig/ctrl/addons/<name>.sh`, if there is one |
+| `notes` | lines written into `.env.example` as comments |
+
+`service.yml` is a plain compose fragment with one top-level key — the service
+name. It stays YAML rather than being generated from JSON so it reads like the
+file it becomes, and so anything compose supports is available without this tool
+learning about it first.
+
+Adding a cabinet is adding a directory. Nothing dispatches on the name.
diff --git a/docs/data/en/station-datagen.md b/docs/data/en/station-datagen.md
index 08ea501..ea5dff3 100644
--- a/docs/data/en/station-datagen.md
+++ b/docs/data/en/station-datagen.md
@@ -1,6 +1,8 @@
 # Datagen
 
-Test data generator using faker. Produces realistic, domain-specific data for testing and development.
+Test data generator. Produces realistic, domain-specific records for testing and
+development, from generators a room writes or that
+[modelgen](#station-modelgen) writes for it.
 
 **Status:** live
 
@@ -8,50 +10,95 @@ Test data generator using faker. Produces realistic, domain-specific data for te
 
 ## What It Does
 
-Datagen generates fake but realistic data. Names, emails, addresses, transactions -- whatever your domain needs. It uses Python's faker library under the hood.
+Datagen hands out instances of a room's models. Core ships the base class, the
+discovery, the HTTP API and the browser UI; the generators themselves belong to
+a room, because what counts as realistic is a property of the domain.
 
-Core datagen is a placeholder. The real work happens in room-specific generators.
+Generation is stdlib `random`, `uuid` and `datetime` — **not** faker, which is
+not a dependency of this repo.
 
 ## Structure
 
 ```
-soleprint/station/tools/datagen/       # Core (base classes, placeholder)
-cfg/<room>/soleprint/station/tools/datagen/  # Room-specific generators
+soleprint/station/tools/datagen/              # base class, api, UI
+cfg/<room>/soleprint/station/tools/datagen/   # the room's generators
 ```
 
 After build, both merge into `gen/<room>/station/tools/datagen/`.
 
-## Pattern
+## The contract
 
-Rooms subclass a base generator and provide domain-specific data factories:
+A generator subclasses `BaseDataGenerator` and defines **one method per model,
+named after it**. There is no registration step: the method name *is* the model
+name.
 
 ```python
-from station.tools.datagen.base import BaseGenerator
+from station.tools.datagen.base import BaseDataGenerator
 
-class RoomDataGenerator(BaseGenerator):
-    def generate_customers(self, count=10):
-        return [self.fake_customer() for _ in range(count)]
+class RoomDataGenerator(BaseDataGenerator):
+    def customer(self, **kwargs):
+        return {"id": str(uuid4()), "name": ..., "email": ..., **kwargs}
 
-    def fake_customer(self):
-        return {
-            "name": self.faker.name(),
-            "email": self.faker.email(),
-            "phone": self.faker.phone_number(),
-        }
+    def invoice(self, customer_id=None, **kwargs):
+        return {"id": str(uuid4()), "customer_id": customer_id, **kwargs}
+```
+
+The base class provides:
+
+| Method | Does |
+| --- | --- |
+| `generate(model, count=1, **kwargs)` | calls the matching method `count` times; `kwargs` pass through to every call |
+| `available_models()` | the method names, which are the model names |
+| `schema()` | override to return a graphgen-compatible schema |
+
+Discovery is by convention too: any `*.py` in the datagen directory whose first
+class ends in `Generator` is loaded and keyed by its filename.
+
+## Generating a generator
+
+Writing one by hand is optional. modelgen's `datagen` target emits the whole
+class from a schema — and when the schema came from spreadsheets, the generated
+class **samples the real rows** rather than inventing values:
+
+```bash
+python -m station.tools.modelgen from-tabular -s ./sheets -o out/ -t datagen
+python -m station.tools.modelgen from-openapi -s api.yaml -o out/ -t datagen
 ```
 
-Each room defines what data it needs. Core provides the faker instance and base class. Rooms provide the factories.
+This is how [shuntgen](#station-shuntgen) fills a generated shunt.
+
+## HTTP API
+
+Mounted under `/station/tools/datagen/`:
+
+| Route | Returns |
+| --- | --- |
+| `GET /` | the browser UI |
+| `GET /api/generators` | loaded generator files and their models |
+| `GET /api/models?generator=` | model names |
+| `POST /api/generate` | `{model, count, generator?, kwargs?}` → the records |
+| `GET /api/schema?generator=` | the generator's schema, if it exposes one |
 
-## Room Configuration
+## Feeding graphgen
 
-Room generators live in `cfg/<room>/soleprint/station/tools/datagen/`. They are fully self-contained -- they define their own models, factories, and output formats.
+A generator that overrides `schema()` is surfaced at `/api/schema` in the format
+[graphgen](#station-graphgen) reads, so the same definition draws the diagram:
 
-The core module provides:
-- Base generator class with faker instance
-- CLI entry point
-- Output formatting (JSON, CSV)
+```python
+def schema(self):
+    return {
+        "models": {
+            "Invoice": {
+                "doc": "A billed order.",
+                "fields": {
+                    "id":          {"type": "UUID", "pk": True},
+                    "customer_id": {"type": "FK:Customer"},
+                    "total":       {"type": "float"},
+                },
+            }
+        }
+    }
+```
 
-Rooms provide:
-- Domain-specific generator subclasses
-- Field definitions and relationships
-- Volume and distribution configuration
+`FK:<Model>` and `M2M:<Model>` are how relations are written. modelgen's
+`datagen` target emits this method for you.
diff --git a/docs/data/en/station-modelgen.md b/docs/data/en/station-modelgen.md
index acfe89d..a66a06a 100644
--- a/docs/data/en/station-modelgen.md
+++ b/docs/data/en/station-modelgen.md
@@ -1,54 +1,111 @@
 # Modelgen
 
-Generates platform-specific models from JSON Schema. Reads schema once, writes models for multiple targets.
+Multi-source, multi-target model generator. Reads a schema from wherever it
+already lives, and writes it out for every stack that needs it.
 
-**Status:** dev
+**Status:** live
 
 ---
 
 ## What It Does
 
-Modelgen takes a JSON Schema definition and produces model code for different platforms:
+Everything passes through one intermediate representation — `ModelDefinition`,
+`FieldDefinition`, `EnumDefinition`. **Loaders** fill it, **generators** emit
+from it, and the two sides do not know about each other. Adding an input means
+one extractor and every output comes with it; adding an output means one
+generator and every input already feeds it.
 
-- **Pydantic** -- Python data validation models
-- **Django ORM** -- Django model classes
-- **Prisma** -- Prisma schema definitions
+```
+ dataclasses ─┐                        ┌─ pydantic
+ Django       │                        ├─ django
+ SQLAlchemy   ├──▶  ModelDefinition ──▶├─ sqlmodel
+ a live DB    │       FieldDefinition  ├─ typescript
+ OpenAPI      │       EnumDefinition   ├─ protobuf
+ CSV/ODS     ─┘                        ├─ prisma
+                                       ├─ strawberry
+                                       ├─ schema (graphgen)
+                                       └─ datagen
+```
 
-One schema, multiple outputs.
+Core is **pure standard library**. It is published as `soleprint-modelgen` and
+installs with no dependencies; live-database extraction is an extra
+(`pip install "soleprint-modelgen[db]"`), and YAML specs need PyYAML.
 
-## Extractors
+## Sources
 
-Modelgen also works in reverse. Extractors read existing codebases and produce a normalized schema representation:
+| Command | Reads |
+| --- | --- |
+| `from-schema` | Python dataclasses in a `schema/` folder |
+| `from-config` | a room's `config.json` |
+| `extract` | a Django or SQLAlchemy codebase (`--framework auto` detects) |
+| `from-db` | a live database, any SQLAlchemy dialect |
+| `from-openapi` | an OpenAPI 3.x / Swagger 2.0 document |
+| `from-tabular` | a directory of `.csv` / `.tsv` / `.ods` spreadsheets |
 
-- **Django extractor** -- reads Django model files
-- **SQLAlchemy extractor** -- reads SQLAlchemy model files
-- **Prisma extractor** -- reads Prisma schema files
+```bash
+python -m station.tools.modelgen from-openapi -s api.yaml -o out/ -t pydantic,typescript,schema
+python -m station.tools.modelgen from-tabular -s ./sheets -o out/ -t pydantic,datagen
+python -m station.tools.modelgen extract -s /path/to/django -o out/ -t prisma
+python -m station.tools.modelgen from-db -u postgresql://… -o out/ -t typescript
+python -m station.tools.modelgen list-formats
+```
 
-Extractors feed into graphgen for visualization.
+### From a spec
 
-## Output
+`components.schemas` (or Swagger's `definitions`) become models. `$ref` chains
+and `allOf` are resolved, enums are materialised as real `Enum` classes so every
+target names them properly, and a referenced object becomes a relation rather
+than a nested type — the same call the database extractor makes, and what keeps
+the generated code valid for every target.
 
-Generated models are written to `gen/<room>/models/`.
+The parse also yields the *operations*, which is what
+[shuntgen](#station-shuntgen) turns into routes.
 
-```
-gen/<room>/models/
-├── pydantic/
-├── django/
-└── prisma/
-```
+### From spreadsheets
 
-## CLI
+One model per CSV file, one per sheet in an ODS workbook. Column types are
+inferred from the values actually present, and a blank cell makes the column
+optional. Keys and relations are inferred by name and then confirmed against the
+data: an `id` column that is not unique is not treated as a key, and
+`customer_id` is only a foreign key if a `customers` sheet came with it.
 
-```bash
-python -m modelgen
-```
+The rows are kept, not just the shape — which is what lets the `datagen` target
+sample real values instead of inventing them.
 
-Reads from `schema.json` (the project source of truth) and writes to the configured output directory.
+ODS is read with `zipfile` and `ElementTree`. No odfpy, no pandas: the
+dependency-free promise is what makes this package publishable on its own.
 
-## Shared Distribution
+## Targets
 
-Modelgen is also distributed as a shared component via `ctrl/spr.py`. This allows other projects to use model generation without running full soleprint.
+`pydantic`, `django`, `sqlmodel`, `typescript` (`ts`), `protobuf` (`proto`),
+`prisma`, `strawberry`, `schema` (`jsonschema`), `datagen`.
 
-## Schema Source
+Two are worth calling out:
+
+- **`schema`** writes the graphgen-compatible `schema.json` — the portable
+  artifact [graphgen](#station-graphgen) and databrowse read directly.
+  Relations come out as `FK:<Model>` and `M2M:<Model>`.
+- **`datagen`** writes a `BaseDataGenerator` subclass for
+  [datagen](#station-datagen), including its `schema()` override. Given
+  spreadsheet rows it samples them; otherwise it synthesises from the types.
+
+Multiple targets in one run get one file each, named `models_<target><ext>`.
+
+## In a build
+
+`build.py` calls modelgen during every room build, writing
+`gen/<room>/models/pydantic/__init__.py` from the room's `config.json`. See
+[Export / Compile](#export).
+
+## Tests
+
+```bash
+cd soleprint/station/tools
+python -m unittest modelgen.tests.test_extractors
+```
 
-The source of truth is `schema.json` at the project root. All model generation starts from this file. Room-specific schema extensions live in `cfg/<room>/models/`.
+stdlib `unittest`, no pytest, and every input is built in a temp directory — the
+tests have to pass with nothing installed and nothing else in the tree. Run them
+from `station/tools/`, not from inside `modelgen/`: the package ships a
+`types.py`, and putting its own directory on `sys.path` shadows the standard
+library module of that name.
diff --git a/docs/data/en/station-shuntgen.md b/docs/data/en/station-shuntgen.md
new file mode 100644
index 0000000..2044d62
--- /dev/null
+++ b/docs/data/en/station-shuntgen.md
@@ -0,0 +1,129 @@
+# Shuntgen
+
+Generates runnable [shunts](#artery-shunts) from the two things people actually
+have: a service contract, or a folder of spreadsheets.
+
+Writing a shunt by hand means copying `artery/shunts/example/` and filling in
+`responses.json` entry by entry. That is fine for three endpoints and untenable
+for eighty — and it is the wrong work anyway, because the endpoints are already
+described in the spec somebody handed you.
+
+```bash
+# a spec you were handed
+python -m station.tools.shuntgen from-openapi -s api.yaml -o artery/shunts/petstore
+
+# sheets a client sent
+python -m station.tools.shuntgen from-tabular -s ./sheets -o artery/shunts/books
+
+python -m station.tools.shuntgen list
+```
+
+Run from `soleprint/`. Also in the browser at `/station/tools/shuntgen/`, where
+you can upload a spec, preview the routes it would serve, and generate.
+
+## What comes out
+
+```
+artery/shunts/<name>/
+  main.py               builds the app from the spec
+  run.py                uvicorn entry point (PORT, or depot/config.json)
+  shunt_runtime.py      vendored runtime — no soleprint import
+  models.py             pydantic, via modelgen
+  datagen_<name>.py     BaseDataGenerator subclass, via modelgen
+  depot/spec.json       routes, collections and schema
+  depot/responses.json  pinned overrides — yours, never overwritten
+  depot/config.json     delays, error rate, prefill — yours, never overwritten
+  depot/data.json       imported rows
+  templates/index.html  config UI
+  README.md
+```
+
+```bash
+cd artery/shunts/books && python run.py
+curl localhost:8098/customers
+```
+
+The routes are built at startup from `spec.json` rather than written out as
+source. That keeps the generated code short enough to read, and puts the
+behaviour in one reviewable place: fixing `runtime.py` fixes every shunt, and
+regenerating is a copy.
+
+## Where a response comes from
+
+First hit wins:
+
+1. `depot/responses.json` — a pinned override, keyed `"METHOD /path"`
+2. the store — rows imported from sheets, plus anything POSTed since
+3. the spec's `example`, if the source document carried one
+4. `datagen_<name>.py`, synthesising from the schema
+5. `{}`
+
+The store is what makes it behave like a service rather than a random-value
+faucet: POST something and GET it back, ask for `/pets/7` and get the pet whose
+id is 7. Collections that arrived with no rows are prefilled with generated
+ones, so the first call answers with something.
+
+## Two sources, one pipeline
+
+Both inputs are [modelgen](#station-modelgen) extractors, so the same shapes
+also generate pydantic, TypeScript, prisma and a
+[graphgen](#station-graphgen) schema:
+
+```bash
+python -m station.tools.modelgen from-openapi -s api.yaml -o out/ -t pydantic,typescript
+python -m station.tools.modelgen from-tabular -s ./sheets -o out/ -t schema,datagen
+```
+
+| Source | Becomes | Routes |
+| --- | --- | --- |
+| OpenAPI 3.x / Swagger 2.0 | one model per schema; enums become real Enums, `$ref` becomes a relation | the operations the document declares |
+| `.csv` / `.tsv` / `.ods` | one model per file or sheet, types inferred per column | five CRUD routes per table |
+
+Keys and relations are inferred by name and then **checked against the data**:
+an `id` column that is not unique is not treated as a key, and `customer_id` is
+only a foreign key if a `customers` sheet came with it.
+
+ODS is read with `zipfile` and `ElementTree` — no odfpy, no pandas — which is
+what lets modelgen stay dependency-free and publishable on its own.
+
+## Control endpoints
+
+Every generated shunt serves these:
+
+| Endpoint | Purpose |
+| --- | --- |
+| `GET /health` | liveness |
+| `GET /mock/spec` | the routes it was built from |
+| `GET /mock/stats` | call counts and row counts |
+| `POST /mock/reset` | restore the imported rows, clear counters |
+| `GET,POST /mock/config` | delays, error rate, `unknown_id`, page size |
+| `GET,POST /mock/responses` | pin an override; set a key to `null` to drop it |
+
+```bash
+# make it slow and flaky, the way the real thing is
+curl -X POST localhost:8098/mock/config \
+  -H 'content-type: application/json' \
+  -d '{"enable_random_delays": true, "error_rate": 0.2}'
+
+# make one call answer something specific
+curl -X POST localhost:8098/mock/responses \
+  -H 'content-type: application/json' \
+  -d '{"GET /customers/1": {"id": 1, "name": "PINNED"}}'
+```
+
+`unknown_id` decides what an unknown key does: `generate` (the default) invents
+a record wearing the id that was asked for; `404` refuses it. Generate by
+default, because a client pointed at a fresh shunt should just work — flip it
+when the error path is what you are testing.
+
+## Dependency containers
+
+`--cabinet postgres,redis` writes a `cabinet.json` declaring what the shunt
+expects. `build.py` composes those services into the room's compose file, and on
+a cluster they install as rig addons of the same name. See
+[Cabinets](#station-cabinets).
+
+## Regenerating
+
+Everything is overwritten except `depot/responses.json` and `depot/config.json`.
+Those two are yours.
diff --git a/docs/data/topics.json b/docs/data/topics.json
index e22d553..ddeaf32 100644
--- a/docs/data/topics.json
+++ b/docs/data/topics.json
@@ -22,8 +22,11 @@
   {"id": "station-datagen", "title": {"en": "↳ Datagen"}, "sub": true},
   {"id": "station-modelgen", "title": {"en": "↳ Modelgen"}, "sub": true},
   {"id": "station-graphgen", "title": {"en": "↳ Graphgen"}, "sub": true},
+  {"id": "station-shuntgen", "title": {"en": "↳ Shuntgen"}, "sub": true},
   {"id": "station-databrowse", "title": {"en": "↳ Databrowse"}, "sub": true},
+  {"id": "station-cabinets", "title": {"en": "↳ Cabinets"}, "sub": true},
 
   {"id": "components", "title": {"en": "Shared Components"}},
+  {"id": "export", "title": {"en": "Export / Compile"}},
   {"id": "deployment", "title": {"en": "Deployment"}}
 ]
diff --git a/soleprint/artery/index.html b/soleprint/artery/index.html
index a35ef6a..093310e 100644
--- a/soleprint/artery/index.html
+++ b/soleprint/artery/index.html
@@ -1,5 +1,5 @@
 <!doctype html>
-<html lang="en">
+<html lang="en" data-theme="soleprint">
     <head>
         <meta charset="UTF-8" />
         <meta name="viewport" content="width=device-width, initial-scale=1.0" />
@@ -14,7 +14,7 @@
                 box-sizing: border-box;
             }
             html {
-                background: #0a0a0a;
+                background: var(--bg);
             }
             body {
                 font-family:
@@ -25,8 +25,8 @@
                 margin: 0 auto;
                 padding: 2rem 1rem;
                 line-height: 1.6;
-                color: #e5e5e5;
-                background: #b91c1c;
+                color: var(--text);
+                background: var(--system-accent);
             }
             header {
                 display: flex;
@@ -51,7 +51,7 @@
                 padding-bottom: 2rem;
             }
             section {
-                background: #0a0a0a;
+                background: var(--bg);
                 padding: 1.5rem;
                 margin: 1.5rem 0;
                 border-radius: 12px;
@@ -59,23 +59,23 @@
             section h2 {
                 margin: 0 0 1rem 0;
                 font-size: 1.2rem;
-                color: #fca5a5;
+                color: var(--system-accent-text);
             }
             .composition {
-                background: #1a1a1a;
-                border: 2px solid #b91c1c;
+                background: var(--surface);
+                border: 2px solid var(--system-accent);
                 padding: 1rem;
                 border-radius: 12px;
             }
             .composition h3 {
                 margin: 0 0 0.75rem 0;
                 font-size: 1.1rem;
-                color: #fca5a5;
+                color: var(--system-accent-text);
             }
             .composition > p {
                 margin: 0 0 1rem 0;
                 font-size: 0.9rem;
-                color: #a3a3a3;
+                color: var(--muted);
             }
             .components {
                 display: grid;
@@ -83,20 +83,20 @@
                 gap: 0.75rem;
             }
             .component {
-                background: #0a0a0a;
-                border: 1px solid #3f3f3f;
+                background: var(--bg);
+                border: 1px solid var(--border-strong);
                 padding: 0.75rem;
                 border-radius: 8px;
             }
             .component h4 {
                 margin: 0 0 0.25rem 0;
                 font-size: 0.95rem;
-                color: #fca5a5;
+                color: var(--system-accent-text);
             }
             .component p {
                 margin: 0;
                 font-size: 0.85rem;
-                color: #a3a3a3;
+                color: var(--muted);
             }
             .veins {
                 display: grid;
@@ -104,8 +104,8 @@
                 gap: 1rem;
             }
             .vein {
-                background: #1a1a1a;
-                border: 1px solid #3f3f3f;
+                background: var(--surface);
+                border: 1px solid var(--border-strong);
                 padding: 1rem;
                 border-radius: 8px;
                 text-align: center;
@@ -113,16 +113,16 @@
                 transition: all 0.15s;
             }
             .vein:hover {
-                background: #2a2a2a;
+                background: var(--border);
             }
             .vein.selected {
-                border-color: #b91c1c;
+                border-color: var(--system-accent);
                 border-width: 2px;
-                background: #1a1a1a;
+                background: var(--surface);
             }
             .vein.active {
-                background: #b91c1c;
-                border-color: #b91c1c;
+                background: var(--system-accent);
+                border-color: var(--system-accent);
             }
             .vein.active h3 {
                 color: white;
@@ -139,12 +139,12 @@
                 cursor: not-allowed;
             }
             .vein.disabled:hover {
-                background: #1a1a1a;
+                background: var(--surface);
             }
             .vein h3 {
                 margin: 0;
                 font-size: 1rem;
-                color: #e5e5e5;
+                color: var(--text);
             }
             .endpoints {
                 list-style: none;
@@ -153,7 +153,7 @@
             }
             .endpoints li {
                 padding: 0.75rem 0;
-                border-bottom: 1px solid #3f3f3f;
+                border-bottom: 1px solid var(--border-strong);
                 display: flex;
                 justify-content: space-between;
                 flex-wrap: wrap;
@@ -164,18 +164,18 @@
             }
             .endpoints code {
                 font-family: monospace;
-                background: #1a1a1a;
+                background: var(--surface);
                 padding: 0.25rem 0.5rem;
                 border-radius: 4px;
-                color: #fca5a5;
+                color: var(--system-accent-text);
             }
             .endpoints .desc {
-                color: #a3a3a3;
+                color: var(--muted);
                 font-size: 0.9rem;
             }
             code {
-                background: #2a2a2a;
-                color: #fca5a5;
+                background: var(--border);
+                color: var(--system-accent-text);
                 padding: 0.1rem 0.3rem;
                 border-radius: 3px;
                 font-size: 0.85rem;
@@ -210,41 +210,41 @@
                 display: block;
                 font-weight: 500;
                 margin-bottom: 0.5rem;
-                color: #e5e5e5;
+                color: var(--text);
             }
             .api-form input[type="text"] {
                 width: 100%;
                 padding: 0.75rem;
-                border: 1px solid #3f3f3f;
+                border: 1px solid var(--border-strong);
                 border-radius: 8px;
                 font-family: monospace;
                 font-size: 0.9rem;
-                background: #1a1a1a;
-                color: #e5e5e5;
+                background: var(--surface);
+                color: var(--text);
             }
             .api-form input[type="text"]:focus,
             .api-form select:focus {
                 outline: none;
-                border-color: #b91c1c;
+                border-color: var(--system-accent);
             }
             .api-form select {
                 width: 100%;
                 padding: 0.75rem;
-                border: 1px solid #3f3f3f;
+                border: 1px solid var(--border-strong);
                 border-radius: 8px;
                 font-size: 0.9rem;
-                background: #1a1a1a;
-                color: #e5e5e5;
+                background: var(--surface);
+                color: var(--text);
                 cursor: pointer;
             }
             .api-form select:disabled {
-                background: #0a0a0a;
-                color: #666;
+                background: var(--bg);
+                color: var(--dim);
                 cursor: not-allowed;
             }
             .api-form input:disabled {
-                background: #0a0a0a;
-                color: #666;
+                background: var(--bg);
+                color: var(--dim);
                 cursor: not-allowed;
             }
             .api-controls {
@@ -254,7 +254,7 @@
                 margin-top: 1rem;
             }
             .api-controls button {
-                background: #b91c1c;
+                background: var(--system-accent);
                 color: white;
                 border: none;
                 padding: 0.75rem 1.5rem;
@@ -271,17 +271,17 @@
                 cursor: not-allowed;
             }
             .tab-button {
-                background: #1a1a1a !important;
-                border: 1px solid #3f3f3f !important;
-                color: #e5e5e5 !important;
+                background: var(--surface) !important;
+                border: 1px solid var(--border-strong) !important;
+                color: var(--text) !important;
             }
             .tab-button:hover {
-                background: #2a2a2a !important;
+                background: var(--border) !important;
             }
             .tab-button.active {
                 border-color: white !important;
                 border-width: 2px !important;
-                background: #b91c1c !important;
+                background: var(--system-accent) !important;
                 color: white !important;
             }
             .tab-button.active:hover {
@@ -291,19 +291,19 @@
                 font-size: 2rem;
                 font-weight: bold;
                 padding: 2rem;
-                color: #e5e5e5;
+                color: var(--text);
                 animation: pulse 2s ease-in-out infinite;
             }
             .epic-status.error {
-                color: #fca5a5;
+                color: var(--system-accent-text);
             }
             @keyframes pulse {
                 0%,
                 100% {
-                    color: #0a0a0a;
+                    color: var(--bg);
                 }
                 50% {
-                    color: #b91c1c;
+                    color: var(--system-accent);
                 }
             }
             .api-controls label {
@@ -312,7 +312,7 @@
                 gap: 0.5rem;
                 font-size: 0.9rem;
                 cursor: pointer;
-                color: #e5e5e5;
+                color: var(--text);
             }
             .output-container {
                 position: relative;
@@ -324,8 +324,8 @@
             }
 
             .output-area {
-                background: #1a1a1a;
-                color: #e5e5e5;
+                background: var(--surface);
+                color: var(--text);
                 padding: 1rem;
                 padding-top: 2.5rem;
                 border-radius: 8px;
@@ -337,7 +337,7 @@
                 position: relative;
             }
             .output-area.error {
-                color: #fca5a5;
+                color: var(--system-accent-text);
             }
             .output-area.scrollable {
                 max-height: 1000px;
@@ -353,7 +353,7 @@
                 margin-top: 1.5rem;
             }
             .attachments-container h3 {
-                color: #fca5a5;
+                color: var(--system-accent-text);
                 margin: 0 0 1rem 0;
                 font-size: 1rem;
             }
@@ -370,11 +370,16 @@
             }
             .attachment-label {
                 font-size: 0.85rem;
-                color: #a3a3a3;
+                color: var(--muted);
                 margin-bottom: 0.5rem;
             }
         </style>
-    </head>
+      <link rel="stylesheet" href="/theme.css">
+  <style>
+    /* Artery keeps its own colour under every theme. */
+    :root { --system-accent: #b91c1c; --system-accent-text: #fca5a5; }
+  </style>
+</head>
     <body>
         <header style="position: relative">
             <!-- Flux capacitor -->
@@ -1824,5 +1829,6 @@
                     }
                 });
         </script>
-    </body>
+      <script src="/theme.js" defer></script>
+</body>
 </html>
diff --git a/soleprint/artery/shunts/mercadopago/api/routes.py b/soleprint/artery/shunts/mercadopago/api/routes.py
index 5b4807c..558357a 100755
--- a/soleprint/artery/shunts/mercadopago/api/routes.py
+++ b/soleprint/artery/shunts/mercadopago/api/routes.py
@@ -7,15 +7,8 @@ from fastapi.responses import JSONResponse
 from typing import Optional, List, Dict, Any
 from pydantic import BaseModel
 
-# Import datagen from ward/tools
-import sys
-from pathlib import Path
-ward_tools_path = Path(__file__).parent.parent.parent.parent.parent / "ward" / "tools"
-sys.path.insert(0, str(ward_tools_path))
-
-from datagen.mercadopago import MercadoPagoDataGenerator
-
-from ..core.config import settings
+from core.config import settings
+from datagen import MercadoPagoDataGenerator
 
 router = APIRouter()
 
diff --git a/soleprint/artery/shunts/mercadopago/datagen.py b/soleprint/artery/shunts/mercadopago/datagen.py
new file mode 100644
index 0000000..00e5a34
--- /dev/null
+++ b/soleprint/artery/shunts/mercadopago/datagen.py
@@ -0,0 +1,182 @@
+"""
+MercadoPago response shapes.
+
+This lived under ward/tools/datagen/ before that tree was renamed to station/,
+and the module was lost in the move — api/routes.py has been importing a path
+that does not exist since. It belongs here rather than back in station/tools:
+a shunt runs as its own process, and its payload shapes are part of it.
+
+Amounts are in whole currency units, matching what the real API returns for
+ARS. Every method is static; the routes hold the state, this holds the shapes.
+"""
+
+import random
+import uuid
+from datetime import datetime, timedelta, timezone
+
+CURRENCY = "ARS"
+SITE = "MLA"  # MercadoPago Argentina
+
+PAYMENT_METHODS = ["visa", "master", "amex", "account_money", "rapipago"]
+PAYMENT_TYPES = ["credit_card", "debit_card", "account_money", "ticket"]
+
+STATUS_DETAIL = {
+    "approved": "accredited",
+    "pending": "pending_contingency",
+    "in_process": "pending_review_manual",
+    "rejected": "cc_rejected_insufficient_amount",
+    "cancelled": "expired",
+}
+
+
+def _now() -> str:
+    return datetime.now(timezone.utc).isoformat()
+
+
+def _later(minutes: int) -> str:
+    return (datetime.now(timezone.utc) + timedelta(minutes=minutes)).isoformat()
+
+
+def _numeric_id() -> int:
+    """A MercadoPago-sized numeric id — the routes look these up as ints."""
+    return random.randint(1_000_000_000, 9_999_999_999)
+
+
+class MercadoPagoDataGenerator:
+    """Builds MercadoPago-shaped payloads for the shunt to hand back."""
+
+    @staticmethod
+    def preference(
+        description: str = "Payment",
+        total: float = 0.0,
+        external_reference: str | None = None,
+    ) -> dict:
+        preference_id = f"{random.randint(100000000, 999999999)}-{uuid.uuid4()}"
+        return {
+            "id": preference_id,
+            "client_id": str(random.randint(1_000_000_000_000_000, 9_999_999_999_999_999)),
+            "collector_id": _numeric_id(),
+            "date_created": _now(),
+            "expires": False,
+            "external_reference": external_reference or "",
+            "init_point": f"https://www.mercadopago.com.ar/checkout/v1/redirect?pref_id={preference_id}",
+            "sandbox_init_point": (
+                f"https://sandbox.mercadopago.com.ar/checkout/v1/redirect?pref_id={preference_id}"
+            ),
+            "items": [
+                {
+                    "id": str(uuid.uuid4()),
+                    "title": description,
+                    "description": description,
+                    "quantity": 1,
+                    "unit_price": total,
+                    "currency_id": CURRENCY,
+                }
+            ],
+            "marketplace": "NONE",
+            "marketplace_fee": 0,
+            "operation_type": "regular_payment",
+            "site_id": SITE,
+            "total_amount": total,
+        }
+
+    @staticmethod
+    def payment(
+        transaction_amount: float = 0.0,
+        description: str = "Payment",
+        status: str = "approved",
+        application_fee: float | None = None,
+    ) -> dict:
+        method = random.choice(PAYMENT_METHODS)
+        fee = round(transaction_amount * 0.0579, 2) if transaction_amount else 0.0
+        return {
+            "id": _numeric_id(),
+            "date_created": _now(),
+            "date_approved": _now() if status == "approved" else None,
+            "date_last_updated": _now(),
+            "money_release_date": _later(60 * 24 * 14) if status == "approved" else None,
+            "operation_type": "regular_payment",
+            "payment_method_id": method,
+            "payment_type_id": random.choice(PAYMENT_TYPES),
+            "status": status,
+            "status_detail": STATUS_DETAIL.get(status, "accredited"),
+            "currency_id": CURRENCY,
+            "description": description,
+            "live_mode": False,
+            "collector_id": _numeric_id(),
+            "payer": {
+                "id": str(_numeric_id()),
+                "email": f"test_user_{random.randint(1000, 99999)}@testuser.com",
+                "identification": {"type": "DNI", "number": str(random.randint(10_000_000, 45_000_000))},
+                "type": "customer",
+            },
+            "transaction_amount": transaction_amount,
+            "transaction_amount_refunded": 0,
+            "installments": 1,
+            "transaction_details": {
+                "net_received_amount": (
+                    round(transaction_amount - fee, 2) if status == "approved" else 0
+                ),
+                "total_paid_amount": transaction_amount,
+                "overpaid_amount": 0,
+                "installment_amount": transaction_amount,
+            },
+            "fee_details": (
+                [{"type": "mercadopago_fee", "amount": fee, "fee_payer": "collector"}]
+                if status == "approved"
+                else []
+            ),
+            "application_fee": application_fee,
+            "captured": status == "approved",
+            "external_reference": None,
+        }
+
+    @staticmethod
+    def merchant_order(
+        preference_id: str = "",
+        total: float = 0.0,
+        paid_amount: float = 0.0,
+    ) -> dict:
+        return {
+            "id": _numeric_id(),
+            "status": "closed" if paid_amount >= total and total else "opened",
+            "external_reference": "",
+            "preference_id": preference_id,
+            "payments": [],
+            "shipments": [],
+            "date_created": _now(),
+            "last_updated": _now(),
+            "site_id": SITE,
+            "total_amount": total,
+            "paid_amount": paid_amount,
+            "refunded_amount": 0,
+            "order_status": "paid" if paid_amount >= total and total else "payment_required",
+        }
+
+    @staticmethod
+    def oauth_token() -> dict:
+        return {
+            "access_token": f"APP_USR-{uuid.uuid4().hex}",
+            "token_type": "Bearer",
+            "expires_in": 15552000,
+            "scope": "offline_access read write",
+            "user_id": _numeric_id(),
+            "refresh_token": f"TG-{uuid.uuid4().hex}",
+            "public_key": f"APP_USR-{uuid.uuid4()}",
+            "live_mode": False,
+        }
+
+    @staticmethod
+    def webhook_notification(topic: str = "payment", resource_id: str = "") -> dict:
+        return {
+            "id": _numeric_id(),
+            "live_mode": False,
+            "type": topic,
+            "date_created": _now(),
+            "application_id": _numeric_id(),
+            "user_id": _numeric_id(),
+            "version": 1,
+            "api_version": "v1",
+            "action": f"{topic}.updated",
+            "data": {"id": str(resource_id)},
+        }
diff --git a/soleprint/artery/shunts/mercadopago/main.py b/soleprint/artery/shunts/mercadopago/main.py
index f9d9a0f..c62cec0 100755
--- a/soleprint/artery/shunts/mercadopago/main.py
+++ b/soleprint/artery/shunts/mercadopago/main.py
@@ -5,8 +5,10 @@ from fastapi import FastAPI, Request
 from fastapi.responses import HTMLResponse
 from fastapi.templating import Jinja2Templates
 from fastapi.middleware.cors import CORSMiddleware
-from .api.routes import router
-from .core.config import settings
+# Absolute imports: a shunt is started from its own directory (`python run.py`),
+# not imported as a package, so relative imports have no parent to resolve.
+from api.routes import router
+from core.config import settings
 
 app = FastAPI(
     title="MercadoPago (MOCK)",
diff --git a/soleprint/atlas/index.html b/soleprint/atlas/index.html
index dea9e62..12332eb 100644
--- a/soleprint/atlas/index.html
+++ b/soleprint/atlas/index.html
@@ -1,5 +1,5 @@
 <!doctype html>
-<html lang="en">
+<html lang="en" data-theme="soleprint">
     <head>
         <meta charset="UTF-8" />
         <meta name="viewport" content="width=device-width, initial-scale=1.0" />
@@ -14,7 +14,7 @@
                 box-sizing: border-box;
             }
             html {
-                background: #0a0a0a;
+                background: var(--bg);
             }
             body {
                 font-family:
@@ -25,7 +25,7 @@
                 margin: 0 auto;
                 padding: 2rem 1rem;
                 line-height: 1.6;
-                color: #e5e5e5;
+                color: var(--text);
                 background: #163528;
             }
             header {
@@ -59,7 +59,7 @@
             section h2 {
                 margin: 0 0 1rem 0;
                 font-size: 1.2rem;
-                color: #86efac;
+                color: var(--system-accent-text);
             }
             .composition {
                 background: #000000;
@@ -70,12 +70,12 @@
             .composition h3 {
                 margin: 0 0 0.75rem 0;
                 font-size: 1.1rem;
-                color: #86efac;
+                color: var(--system-accent-text);
             }
             .composition > p {
                 margin: 0 0 1rem 0;
                 font-size: 0.9rem;
-                color: #a3a3a3;
+                color: var(--muted);
             }
             .components {
                 display: grid;
@@ -83,7 +83,7 @@
                 gap: 0.75rem;
             }
             .component {
-                background: #0a0a0a;
+                background: var(--bg);
                 border: 1px solid #6b665e;
                 padding: 0.75rem;
                 border-radius: 8px;
@@ -91,12 +91,12 @@
             .component h4 {
                 margin: 0 0 0.25rem 0;
                 font-size: 0.95rem;
-                color: #86efac;
+                color: var(--system-accent-text);
             }
             .component p {
                 margin: 0;
                 font-size: 0.85rem;
-                color: #a3a3a3;
+                color: var(--muted);
             }
             .books {
                 list-style: none;
@@ -114,7 +114,7 @@
                 border-bottom: none;
             }
             .books a {
-                color: #86efac;
+                color: var(--system-accent-text);
                 text-decoration: none;
                 font-weight: 500;
             }
@@ -138,7 +138,12 @@
                 opacity: 0.5;
             }
         </style>
-    </head>
+      <link rel="stylesheet" href="/theme.css">
+  <style>
+    /* Atlas keeps its own colour under every theme. */
+    :root { --system-accent: #15803d; --system-accent-text: #86efac; }
+  </style>
+</head>
     <body>
         <header style="position: relative">
             <!-- Open book -->
@@ -265,5 +270,6 @@
             {% if soleprint_url %}<a href="{{ soleprint_url }}">← Soleprint</a
             >{% else %}<span class="disabled">← Soleprint</span>{% endif %}
         </footer>
-    </body>
+      <script src="/theme.js" defer></script>
+</body>
 </html>
diff --git a/soleprint/common/theme/theme.js b/soleprint/common/theme/theme.js
new file mode 100644
index 0000000..d24c350
--- /dev/null
+++ b/soleprint/common/theme/theme.js
@@ -0,0 +1,118 @@
+/* Theme selection, and the toggle that drives it.
+ *
+ * Served by run.py at /theme.js, next to /theme.css. Include both and a page
+ * is themed; there is nothing else to wire.
+ *
+ *   <link rel="stylesheet" href="/theme.css">
+ *   <script src="/theme.js" defer></script>
+ *
+ * Resolution order, strongest first:
+ *   1. ?theme=mcrn          — a link that carries its own theme
+ *   2. localStorage         — what this browser last chose
+ *   3. <html data-theme>    — what the page was served with
+ *   4. the server default   — framework.theme in cfg/config.json
+ *
+ * The attribute is set before first paint when this script is loaded in the
+ * head; with `defer` the page renders once in the served theme and then
+ * switches, which is why run.py stamps data-theme into the served HTML.
+ */
+(function () {
+    "use strict";
+
+    var THEMES = ["soleprint", "mcrn"];
+    var KEY = "spr-theme";
+    var root = document.documentElement;
+
+    function fromQuery() {
+        var match = /[?&]theme=([^&#]+)/.exec(window.location.search);
+        return match ? decodeURIComponent(match[1]) : null;
+    }
+
+    function stored() {
+        try {
+            return window.localStorage.getItem(KEY);
+        } catch (e) {
+            // Private mode and file:// origins throw on access rather than
+            // returning null, and a theme is not worth breaking a page over.
+            return null;
+        }
+    }
+
+    function resolve() {
+        var candidates = [fromQuery(), stored(), root.getAttribute("data-theme")];
+        for (var i = 0; i < candidates.length; i++) {
+            if (candidates[i] && THEMES.indexOf(candidates[i]) !== -1) {
+                return candidates[i];
+            }
+        }
+        return THEMES[0];
+    }
+
+    function apply(theme, persist) {
+        root.setAttribute("data-theme", theme);
+        if (persist) {
+            try {
+                window.localStorage.setItem(KEY, theme);
+            } catch (e) {
+                /* see stored() */
+            }
+        }
+        var buttons = document.querySelectorAll("#spr-theme-toggle button");
+        for (var i = 0; i < buttons.length; i++) {
+            buttons[i].setAttribute(
+                "aria-pressed",
+                buttons[i].dataset.theme === theme ? "true" : "false"
+            );
+        }
+        window.dispatchEvent(new CustomEvent("spr:theme", { detail: theme }));
+    }
+
+    function buildToggle() {
+        if (document.getElementById("spr-theme-toggle")) return;
+        // Opt out with <body data-theme-toggle="off"> — the shunt config UIs
+        // and any embedded view want the theme without the chrome.
+        if (document.body.dataset.themeToggle === "off") return;
+
+        var box = document.createElement("div");
+        box.id = "spr-theme-toggle";
+        box.setAttribute("role", "group");
+        box.setAttribute("aria-label", "Theme");
+
+        THEMES.forEach(function (theme) {
+            var button = document.createElement("button");
+            button.type = "button";
+            button.dataset.theme = theme;
+            button.textContent = theme === "mcrn" ? "MCRN" : "SPR";
+            button.title = "Switch to the " + theme + " theme";
+            button.addEventListener("click", function () {
+                apply(theme, true);
+            });
+            box.appendChild(button);
+        });
+
+        document.body.appendChild(box);
+    }
+
+    // Set the attribute immediately; the toggle needs a body to attach to.
+    apply(resolve(), false);
+
+    if (document.readyState === "loading") {
+        document.addEventListener("DOMContentLoaded", function () {
+            buildToggle();
+            apply(root.getAttribute("data-theme"), false);
+        });
+    } else {
+        buildToggle();
+        apply(root.getAttribute("data-theme"), false);
+    }
+
+    window.sprTheme = {
+        get: function () {
+            return root.getAttribute("data-theme");
+        },
+        set: function (theme) {
+            if (THEMES.indexOf(theme) !== -1) apply(theme, true);
+        },
+        themes: THEMES.slice(),
+    };
+})();
diff --git a/soleprint/common/theme/themes/mcrn.css b/soleprint/common/theme/themes/mcrn.css
new file mode 100644
index 0000000..6861504
--- /dev/null
+++ b/soleprint/common/theme/themes/mcrn.css
@@ -0,0 +1,110 @@
+/* MCRN — the terminal read of the Expanse aesthetic, as built at mariano.mcrn.ar.
+ *
+ * The defining choices, all of them load-bearing:
+ *   - zero corner radius, everywhere, including inputs and buttons
+ *   - one hairline border colour and one accent; nothing in between
+ *   - monospace for everything, not just code
+ *   - headings are uppercase, letterspaced, unbolded, and ruled underneath
+ *   - the only hover is a burnt-orange border and a glow behind it
+ *
+ * Values are lifted from ~/wdir/mcrn.ar/css/mcrn.css rather than approximated,
+ * so the two sites read as one system.
+ */
+
+[data-theme="mcrn"] {
+    --bg: #0a0a0a;
+    --bg-2: #141414;
+    --surface: #1a1a1a;
+    --surface-raised: #202020;
+    --border: #2a2a2a;
+    --border-strong: #3d3d3d;
+
+    --text: #e0e0e0;
+    --muted: #888;
+    --dim: #555;
+
+    --accent: #d35400;
+    --accent-dim: #c0392b;
+    --accent-text: #d35400;
+    --glow: rgba(211, 84, 0, 0.3);
+
+    --status-ok: #2ecc71;
+    --status-info: #5dade2;
+    --status-warn: #f39c12;
+    --status-error: #e74c3c;
+    --status-idle: #555;
+
+    /* Square. This is the single most recognisable thing about the theme, so
+     * it applies to the small radii too — a 4px input in a 0px page reads as a
+     * mistake rather than a detail. */
+    --radius-sm: 0;
+    --radius: 0;
+    --radius-lg: 0;
+    --radius-xl: 0;
+
+    --font-ui: "JetBrains Mono", "Fira Code", "SF Mono", monospace;
+    --font-mono: "JetBrains Mono", "Fira Code", "SF Mono", monospace;
+    --font-heading: "JetBrains Mono", "Fira Code", "SF Mono", monospace;
+    --heading-transform: uppercase;
+    --heading-spacing: 0.1em;
+    --heading-weight: 400;
+    --label-spacing: 0.05em;
+
+    --speed-fast: 0.15s;
+    --speed: 0.2s;
+
+    /* Glow instead of lift: this theme never moves anything on hover. */
+    --hover-shadow: 0 0 20px var(--glow);
+    --hover-lift: none;
+    --focus-shadow: 0 0 10px var(--glow);
+}
+
+/* Section headings carry a rule, and the rule is part of the type. */
+[data-theme="mcrn"] h2 {
+    color: var(--system-accent-text, var(--accent-text));
+    padding-bottom: var(--space-2);
+    border-bottom: var(--hairline) solid var(--border);
+}
+
+/* Prompt bullets. Lists in this theme are terminal output, not prose. */
+[data-theme="mcrn"] ul:not([class*="reset"]) > li::marker {
+    content: "";
+}
+
+[data-theme="mcrn"] .prompt-list {
+    list-style: none;
+    padding-left: 0;
+}
+
+[data-theme="mcrn"] .prompt-list > li {
+    position: relative;
+    padding-left: 1.25rem;
+}
+
+[data-theme="mcrn"] .prompt-list > li::before {
+    content: ">";
+    position: absolute;
+    left: 0;
+    color: var(--accent);
+    font-weight: 600;
+}
+
+/* The active state is a solid fill with the page colour punched out of it —
+ * the segmented-control move from the portfolio's language toggle. */
+[data-theme="mcrn"] button[aria-pressed="true"],
+[data-theme="mcrn"] .active,
+[data-theme="mcrn"] .selected {
+    background: var(--accent);
+    color: var(--bg);
+    border-color: var(--accent);
+}
+
+[data-theme="mcrn"] .card:hover,
+[data-theme="mcrn"] .panel:hover,
+[data-theme="mcrn"] .system-card:hover,
+[data-theme="mcrn"] .tool-card:hover,
+[data-theme="mcrn"] .model-card:hover {
+    border-color: var(--system-accent, var(--accent));
+    box-shadow: 0 0 20px var(--glow);
+    transform: none;
+}
diff --git a/soleprint/common/theme/themes/soleprint.css b/soleprint/common/theme/themes/soleprint.css
new file mode 100644
index 0000000..afbe6b7
--- /dev/null
+++ b/soleprint/common/theme/themes/soleprint.css
@@ -0,0 +1,113 @@
+/* Soleprint — minimal, rounded, neon.
+ *
+ * The surface ramp and text colours come from common/ui/src/tokens.css, which
+ * is the most considered palette in the repo: near-black with a violet cast
+ * (#0d0d0f -> #26262f) rather than flat grey. The accent is the amber the brand
+ * page has always used (#d4a574) but which the token file never carried, so
+ * this is where the two finally agree.
+ *
+ * "Neon" here means light around an edge, not saturated fills: a 1px halo in
+ * the accent, translucent badge fills at 18/66 alpha, and a small lift on
+ * hover. Restrained enough to sit under dense tool UIs for an hour.
+ */
+
+[data-theme="soleprint"] {
+    --bg: #0d0d0f;
+    --bg-2: #16161a;
+    --surface: #16161a;
+    --surface-raised: #1e1e24;
+    --border: #2e2e38;
+    --border-strong: #3d3d4a;
+
+    --text: #e8e8f0;
+    --muted: #8888a0;
+    --dim: #555568;
+
+    --accent: #d4a574;
+    --accent-dim: #b8956a;
+    --accent-text: #e0b98d; /* lifted off the fill colour so small text holds up */
+    --glow: rgba(212, 165, 116, 0.32);
+
+    --status-ok: #3ecf8e;
+    --status-info: #4f9cf9;
+    --status-warn: #f5a623;
+    --status-error: #f06565;
+    --status-idle: #555568;
+
+    /* Rounded but restrained — nothing above 12px, so panels read as soft
+     * rather than as pills. */
+    --radius-sm: 4px;
+    --radius: 6px;
+    --radius-lg: 8px;
+    --radius-xl: 12px;
+
+    --font-ui: "Inter", system-ui, -apple-system, sans-serif;
+    --font-mono: "JetBrains Mono", "Fira Code", monospace;
+    --font-heading: "Inter", system-ui, sans-serif;
+    --heading-transform: none;
+    --heading-spacing: 0.02em;
+    --heading-weight: 600;
+    --label-spacing: 0.04em;
+
+    --speed-fast: 0.12s;
+    --speed: 0.2s;
+
+    --hover-shadow: 0 4px 14px rgba(0, 0, 0, 0.45), 0 0 0 1px var(--accent);
+    --hover-lift: translateY(-2px);
+    --focus-shadow: 0 0 0 2px var(--glow);
+}
+
+[data-theme="soleprint"] .card:hover,
+[data-theme="soleprint"] .panel:hover,
+[data-theme="soleprint"] .system-card:hover,
+[data-theme="soleprint"] .tool-card:hover,
+[data-theme="soleprint"] .model-card:hover {
+    border-color: var(--system-accent, var(--accent));
+    box-shadow: 0 4px 14px rgba(0, 0, 0, 0.45),
+                0 0 0 1px var(--system-accent, var(--accent));
+    transform: translateY(-2px);
+}
+
+[data-theme="soleprint"] button[aria-pressed="true"],
+[data-theme="soleprint"] .active,
+[data-theme="soleprint"] .selected {
+    border-color: var(--accent);
+    color: var(--bg);
+    background: linear-gradient(135deg, var(--accent), var(--accent-dim));
+}
+
+/* Uppercase micro-labels — the recurring motif across the station tools. */
+[data-theme="soleprint"] .label,
+[data-theme="soleprint"] .panel-title {
+    font-size: var(--font-size-sm);
+    font-weight: 600;
+    text-transform: uppercase;
+    letter-spacing: var(--label-spacing);
+    color: var(--muted);
+}
+
+/* Translucent badges, the <hex>18 fill / <hex>66 border pattern graphgen
+ * already uses for pk/fk/m2m chips. */
+[data-theme="soleprint"] .badge {
+    border-radius: var(--radius-sm);
+    padding: 1px 6px;
+    font-family: var(--font-mono);
+    font-size: 10px;
+    letter-spacing: 0.03em;
+    background: #d4a57418;
+    border: 1px solid #d4a57466;
+    color: var(--accent-text);
+}
+
+/* The one animated state, carried over from common/ui's tokens.css. */
+@keyframes spr-waiting-glow {
+    0%   { box-shadow: 0 0 3px 1px var(--status-info); }
+    33%  { box-shadow: 0 0 3px 1px var(--status-ok); }
+    66%  { box-shadow: 0 0 3px 1px var(--status-warn); }
+    100% { box-shadow: 0 0 3px 1px var(--status-info); }
+}
+
+[data-theme="soleprint"] .waiting {
+    animation: spr-waiting-glow 2s linear infinite;
+    outline: 1px solid transparent;
+}
diff --git a/soleprint/common/theme/tokens.css b/soleprint/common/theme/tokens.css
new file mode 100644
index 0000000..d0289d9
--- /dev/null
+++ b/soleprint/common/theme/tokens.css
@@ -0,0 +1,217 @@
+/* Soleprint theme contract — the variable names every page may rely on.
+ *
+ * This file declares the vocabulary and a neutral default. It sets no colours
+ * of its own worth looking at: themes/*.css supply those, scoped to
+ * [data-theme="..."] on <html>, and theme.js decides which one is active.
+ *
+ * Two naming families existed before this file and both are still in use, so
+ * both are answered here rather than renamed across a dozen templates:
+ *
+ *   --bg / --surface / --border / --text / --muted / --amber
+ *       the station tool templates and the docs site
+ *   --surface-0..3 / --text-primary / --text-secondary / --panel-radius
+ *       common/ui's Vue component library
+ *
+ * The theme files set the first family; the aliases at the bottom derive the
+ * second from it. A page that uses either name gets the same colour, and a
+ * theme author has one set of values to fill in.
+ *
+ * Served by run.py at /theme.css together with the theme files — see the
+ * handler beside /sidebar.css.
+ */
+
+@import url("https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600&family=JetBrains+Mono:wght@400;600&display=swap");
+
+:root {
+    /* ── surfaces ─────────────────────────────────────────────────────── */
+    --bg: #0a0a0a;
+    --bg-2: #141414;
+    --surface: #1a1a1a;
+    --surface-raised: #242424;
+    --border: #333;
+    --border-strong: #4a4a4a;
+
+    /* ── text ─────────────────────────────────────────────────────────── */
+    --text: #e5e5e5;
+    --muted: #a3a3a3;
+    --dim: #666;
+
+    /* ── accent ───────────────────────────────────────────────────────── */
+    --accent: #d4a574;
+    --accent-dim: #b8956a;
+    --accent-text: #d4a574; /* accent legible on --bg, where the fill is not */
+    --glow: rgba(212, 165, 116, 0.3);
+
+    /* Each subsystem keeps its own colour under every theme, so a page still
+     * announces which of artery / atlas / station you are looking at. Pages set
+     * --system-accent; this is the fallback for those that do not. */
+    --system-accent: var(--accent);
+    --system-accent-text: var(--accent-text);
+
+    /* ── status ───────────────────────────────────────────────────────── */
+    --status-ok: #3ecf8e;
+    --status-info: #4f9cf9;
+    --status-warn: #f5a623;
+    --status-error: #f06565;
+    --status-idle: #555568;
+
+    /* ── shape ────────────────────────────────────────────────────────── */
+    --radius-sm: 4px;
+    --radius: 6px;
+    --radius-lg: 8px;
+    --radius-xl: 12px;
+    --hairline: 1px;
+
+    /* ── type ─────────────────────────────────────────────────────────── */
+    --font-ui: "Inter", system-ui, -apple-system, sans-serif;
+    --font-mono: "JetBrains Mono", "Fira Code", "SF Mono", monospace;
+    --font-heading: var(--font-ui);
+    --font-size-sm: 11px;
+    --font-size-base: 13px;
+    --font-size-lg: 15px;
+    --heading-transform: none;
+    --heading-spacing: 0;
+    --heading-weight: 600;
+    --label-spacing: 0.04em;
+
+    /* ── space ────────────────────────────────────────────────────────── */
+    --space-1: 4px;
+    --space-2: 8px;
+    --space-3: 12px;
+    --space-4: 16px;
+    --space-6: 24px;
+    --space-8: 32px;
+
+    /* ── motion ───────────────────────────────────────────────────────── */
+    --speed-fast: 0.12s;
+    --speed: 0.2s;
+    --ease: ease;
+
+    /* Themes differ most in how a surface reacts, not in what colour it is.
+     * Both hover treatments are declared here so a page writes one rule and
+     * the theme decides whether it lifts, glows, or both. */
+    --hover-shadow: 0 4px 12px var(--glow);
+    --hover-lift: translateY(-2px);
+    --focus-shadow: 0 0 0 1px var(--accent);
+
+    /* ── aliases for names already in use ─────────────────────────────── */
+
+    /* The station tool templates and the docs site call the accent "amber". */
+    --amber: var(--accent);
+    --amber-dim: var(--accent-dim);
+
+    /* ── aliases for common/ui's token names ──────────────────────────── */
+    --surface-0: var(--bg);
+    --surface-1: var(--surface);
+    --surface-2: var(--surface-raised);
+    --surface-3: var(--border);
+    --text-primary: var(--text);
+    --text-secondary: var(--muted);
+    --text-dim: var(--dim);
+    --panel-radius: var(--radius);
+    --panel-border: var(--hairline) solid var(--border);
+    --panel-header-height: 36px;
+    --status-live: var(--status-ok);
+    --status-processing: var(--status-info);
+    --status-escalating: var(--status-warn);
+}
+
+/* ── element defaults ─────────────────────────────────────────────────── */
+
+body {
+    background: var(--bg);
+    color: var(--text);
+    font-family: var(--font-ui);
+    line-height: 1.6;
+}
+
+h1, h2, h3, h4, h5, h6 {
+    font-family: var(--font-heading);
+    font-weight: var(--heading-weight);
+    text-transform: var(--heading-transform);
+    letter-spacing: var(--heading-spacing);
+}
+
+code, pre, kbd, samp {
+    font-family: var(--font-mono);
+}
+
+a {
+    color: var(--accent-text);
+}
+
+button {
+    background: var(--surface-raised);
+    color: var(--text);
+    border: var(--hairline) solid var(--border);
+    border-radius: var(--radius);
+    font-family: inherit;
+    cursor: pointer;
+    transition: border-color var(--speed-fast) var(--ease),
+                color var(--speed-fast) var(--ease),
+                background var(--speed-fast) var(--ease);
+}
+
+button:hover:not(:disabled) {
+    border-color: var(--accent);
+    color: var(--accent-text);
+}
+
+button:disabled {
+    opacity: 0.4;
+    cursor: default;
+}
+
+input, select, textarea {
+    background: var(--bg);
+    color: var(--text);
+    border: var(--hairline) solid var(--border);
+    border-radius: var(--radius-sm);
+    font-family: inherit;
+}
+
+input:focus, select:focus, textarea:focus {
+    outline: none;
+    border-color: var(--accent);
+    box-shadow: var(--focus-shadow);
+}
+
+::-webkit-scrollbar { width: 10px; height: 10px; }
+::-webkit-scrollbar-thumb { background: var(--border); border-radius: 5px; }
+::-webkit-scrollbar-track { background: transparent; }
+
+/* The theme toggle theme.js injects. Fixed rather than placed, so it needs no
+ * cooperation from the page it lands on. */
+#spr-theme-toggle {
+    position: fixed;
+    right: var(--space-3);
+    bottom: var(--space-3);
+    z-index: 99998;
+    display: flex;
+    gap: 0;
+    border: var(--hairline) solid var(--border);
+    border-radius: var(--radius);
+    overflow: hidden;
+    background: var(--surface);
+    font-family: var(--font-mono);
+    font-size: 10px;
+}
+
+#spr-theme-toggle button {
+    border: none;
+    border-radius: 0;
+    background: var(--surface);
+    color: var(--dim);
+    padding: var(--space-1) var(--space-2);
+    text-transform: uppercase;
+    letter-spacing: var(--label-spacing);
+}
+
+#spr-theme-toggle button + button {
+    border-left: var(--hairline) solid var(--border);
+}
+
+#spr-theme-toggle button[aria-pressed="true"] {
+    background: var(--accent);
+    color: var(--bg);
+}
diff --git a/soleprint/index.html b/soleprint/index.html
index fba6b0a..a06bd59 100644
--- a/soleprint/index.html
+++ b/soleprint/index.html
@@ -1,5 +1,5 @@
 <!doctype html>
-<html lang="en">
+<html lang="en" data-theme="soleprint">
     <head>
         <meta charset="UTF-8" />
         <meta name="viewport" content="width=device-width, initial-scale=1.0" />
@@ -14,7 +14,7 @@
                 box-sizing: border-box;
             }
             html {
-                background: #0a0a0a;
+                background: var(--bg);
             }
             body {
                 font-family:
@@ -25,8 +25,8 @@
                 margin: 0 auto;
                 padding: 2rem 1rem;
                 line-height: 1.6;
-                color: #e5e5e5;
-                background: #0a0a0a;
+                color: var(--text);
+                background: var(--bg);
             }
             /* Sidebar styles */
             .sidebar {
@@ -35,8 +35,8 @@
                 left: 0;
                 width: 60px;
                 height: 100vh;
-                background: #1a1a1a;
-                border-right: 1px solid #333;
+                background: var(--surface);
+                border-right: 1px solid var(--border);
                 display: flex;
                 flex-direction: column;
                 align-items: center;
@@ -52,16 +52,16 @@
                 border-radius: 8px;
                 margin-bottom: 0.5rem;
                 text-decoration: none;
-                color: #a3a3a3;
+                color: var(--muted);
                 transition: all 0.2s;
             }
             a.sidebar-item:hover {
-                background: #333;
+                background: var(--border);
                 color: white;
             }
             .sidebar-item.active {
-                background: #d4a574;
-                color: #0a0a0a;
+                background: var(--accent);
+                color: var(--bg);
             }
             .sidebar-item svg {
                 width: 24px;
@@ -70,7 +70,7 @@
             .sidebar-divider {
                 width: 32px;
                 height: 1px;
-                background: #333;
+                background: var(--border);
                 margin: 0.5rem 0;
             }
             .sidebar-icon {
@@ -89,7 +89,7 @@
             .sidebar-item .tooltip {
                 position: absolute;
                 left: 70px;
-                background: #333;
+                background: var(--border);
                 color: white;
                 padding: 0.5rem 0.75rem;
                 border-radius: 4px;
@@ -121,18 +121,18 @@
                 color: white;
             }
             .tagline {
-                color: #a3a3a3;
+                color: var(--muted);
                 margin-bottom: 2rem;
-                border-bottom: 1px solid #333;
+                border-bottom: 1px solid var(--border);
                 padding-bottom: 2rem;
             }
             .mission {
-                background: #1a1a1a;
-                border-left: 3px solid #d4a574;
+                background: var(--surface);
+                border-left: 3px solid var(--accent);
                 padding: 1rem 1.5rem;
                 margin: 2rem 0;
                 border-radius: 0 8px 8px 0;
-                color: #d4a574;
+                color: var(--accent);
             }
             .systems {
                 display: grid;
@@ -171,11 +171,11 @@
             .system-info p {
                 margin: 0;
                 font-size: 0.9rem;
-                color: #a3a3a3;
+                color: var(--muted);
             }
 
             .artery {
-                background: #1a1a1a;
+                background: var(--surface);
                 border: 1px solid #b91c1c;
             }
             .artery h2 {
@@ -186,7 +186,7 @@
             }
 
             .atlas {
-                background: #1a1a1a;
+                background: var(--surface);
                 border: 1px solid #15803d;
             }
             .atlas h2 {
@@ -197,7 +197,7 @@
             }
 
             .station {
-                background: #1a1a1a;
+                background: var(--surface);
                 border: 1px solid #1d4ed8;
             }
             .station h2 {
@@ -210,9 +210,9 @@
             footer {
                 margin-top: 3rem;
                 padding-top: 1.5rem;
-                border-top: 1px solid #333;
+                border-top: 1px solid var(--border);
                 font-size: 0.85rem;
-                color: #666;
+                color: var(--dim);
             }
 
             .showcase-container {
@@ -224,8 +224,8 @@
             }
             .showcase-link {
                 display: inline-block;
-                background: linear-gradient(135deg, #d4a574, #b8956a);
-                color: #0a0a0a;
+                background: linear-gradient(135deg, var(--accent), var(--accent-dim));
+                color: var(--bg);
                 padding: 0.75rem 1.5rem;
                 border-radius: 8px;
                 text-decoration: none;
@@ -237,19 +237,20 @@
                 box-shadow: 0 4px 12px rgba(212, 165, 116, 0.3);
             }
             .showcase-hint {
-                color: #666;
+                color: var(--dim);
                 font-size: 0.8rem;
                 text-decoration: none;
             }
             .showcase-hint:hover {
-                color: #d4a574;
+                color: var(--accent);
             }
         </style>
         {% if managed %}
         <link rel="stylesheet" href="/sidebar.css">
         <script src="/sidebar.js"></script>
         {% endif %}
-    </head>
+      <link rel="stylesheet" href="/theme.css">
+</head>
     <body{% if managed %} class="has-sidebar"{% endif %}>
 
         <header>
@@ -428,5 +429,6 @@
         </div>
 
         <footer>soleprint</footer>
-    </body>
+      <script src="/theme.js" defer></script>
+</body>
 </html>
diff --git a/soleprint/requirements.txt b/soleprint/requirements.txt
index c66a860..b151a64 100644
--- a/soleprint/requirements.txt
+++ b/soleprint/requirements.txt
@@ -5,6 +5,12 @@ pydantic>=2.5.0
 pydantic-settings>=2.0.0
 httpx>=0.25.0
 jinja2>=3.1.0
+# YAML: OpenAPI specs for shuntgen, and compose fragments for cabinets.
+# modelgen keeps this optional (it imports it lazily) so the pip package stays
+# dependency-free; the server always has it.
+pyyaml>=6.0
+# Multipart form parsing — file uploads in shuntgen's UI.
+python-multipart>=0.0.9
 
 # Database (databrowse)
 sqlalchemy>=2.0.0
diff --git a/soleprint/run.py b/soleprint/run.py
index 68cd2d1..4414422 100644
--- a/soleprint/run.py
+++ b/soleprint/run.py
@@ -249,19 +249,41 @@ def load_config() -> dict:
     return {}
 
 
+class SafeDict(dict):
+    """A dict whose missing keys read as empty rather than exploding a template.
+
+    The landing pages ask for two levels at once — `components.composed.title`.
+    Jinja tolerates one missing level (it returns Undefined, and `or 'Desk'`
+    catches it) but not two: attribute access on Undefined raises, and the
+    whole page 500s.
+
+    That is not hypothetical. cfg/config.json is written into a room by
+    build.py, so it does not exist in the source tree at all, and running
+    `python run.py` from soleprint/ — the documented way to develop — took
+    /station/ down every time.
+    """
+
+    def __getattr__(self, name: str):
+        # The dict's own contents win; only genuinely absent keys become empty.
+        if name in self:
+            value = self[name]
+            return SafeDict(value) if isinstance(value, dict) else value
+        return SafeDict()
+
+
 def get_system_config(system_key: str) -> dict:
     """Get system configuration by key (data_flow, documentation, execution)."""
     config = load_config()
     for system in config.get("systems", []):
         if system.get("key") == system_key:
-            return system
-    return {}
+            return SafeDict(system)
+    return SafeDict()
 
 
 def get_components(system_key: str) -> dict:
     """Get component definitions for a system."""
     config = load_config()
-    return config.get("components", {}).get(system_key, {})
+    return SafeDict(config.get("components", {}).get(system_key, {}))
 
 
 def load_data(filename: str) -> list[dict]:
@@ -461,6 +483,41 @@ def atlas_route(path: str):
 # === Station ===
 
 
+def load_station_cabinets() -> list[dict]:
+    """The dependency containers this room switched on.
+
+    Same two-step as artery's shunts: what the room declared, else what is on
+    disk. The room's list is the honest answer — the catalog holds every
+    cabinet that could be used, not the ones that were.
+    """
+    declared = load_data("cabinets.json")
+    catalog = SPR_ROOT / "station" / "cabinets"
+
+    if declared:
+        cabinets = declared
+    else:
+        cabinets = [
+            {"name": path.name}
+            for path in sorted(catalog.iterdir())
+            if path.is_dir() and not path.name.startswith(("_", "."))
+        ] if catalog.exists() else []
+
+    for cabinet in cabinets:
+        name = cabinet.get("name", "")
+        definition_path = catalog / name / "cabinet.json"
+        if definition_path.exists():
+            try:
+                definition = json.loads(definition_path.read_text())
+                for key in ("title", "description", "image", "rig_addon"):
+                    cabinet.setdefault(key, definition.get(key))
+            except (OSError, ValueError):
+                pass
+        cabinet.setdefault("slug", name)
+        cabinet.setdefault("title", name.replace("-", " ").title())
+        cabinet.setdefault("status", "declared" if declared else "available")
+    return cabinets
+
+
 @app.get("/station", response_class=HTMLResponse)
 @app.get("/station/", response_class=HTMLResponse)
 def station_index(request: Request):
@@ -486,6 +543,7 @@ def station_index(request: Request):
             d["slug"] = d["name"]
             d["title"] = d["name"].replace("-", " ").title()
             d["status"] = "ready"
+        cabinets = load_station_cabinets()
         from jinja2 import Template
 
         template = Template(html_path.read_text())
@@ -497,6 +555,7 @@ def station_index(request: Request):
                 tools=tools,
                 monitors=monitors,
                 desks=desks,
+                cabinets=cabinets,
                 soleprint_url="/",
             )
         )
@@ -512,24 +571,18 @@ def station_index(request: Request):
     )
 
 
-# Mount station tool routers
-try:
-    from station.tools.tester.api import router as tester_router
-    app.include_router(tester_router, prefix="/station")
-except ImportError as e:
-    print(f"Warning: Could not load tester router: {e}")
-
-try:
-    from station.tools.graphgen.api import router as graphgen_router
-    app.include_router(graphgen_router, prefix="/station")
-except ImportError as e:
-    print(f"Warning: Could not load graphgen router: {e}")
-
-try:
-    from station.tools.datagen.api import router as datagen_router
-    app.include_router(datagen_router, prefix="/station")
-except ImportError as e:
-    print(f"Warning: Could not load datagen router: {e}")
+# Mount station tool routers.
+#
+# Broad except on purpose: a tool that cannot load should cost you that tool,
+# not the server. Route registration raises more than ImportError — FastAPI
+# turns a missing optional dependency into a RuntimeError at decoration time —
+# and catching only ImportError meant one such tool took the whole app down.
+for _tool in ("tester", "graphgen", "datagen", "shuntgen"):
+    try:
+        _module = importlib.import_module(f"station.tools.{_tool}.api")
+        app.include_router(_module.router, prefix="/station")
+    except Exception as e:
+        print(f"Warning: Could not load {_tool} router: {e}")
 
 
 @app.get("/station/{path:path}")
@@ -541,6 +594,67 @@ def station_route(path: str):
 # === Sidebar Wrapper (served at /spr/* when proxied) ===
 
 
+# === Theme ===
+#
+# One stylesheet for every page, served the same way the sidebar is. tokens.css
+# declares the variables and both theme files ship in the same response, so a
+# page can switch themes without a second request and without FOUC.
+
+
+def get_default_theme() -> str:
+    """The theme a page is served in, before the browser has an opinion."""
+    framework = load_config().get("framework", {})
+    theme = framework.get("theme", "soleprint")
+    return theme if theme in ("soleprint", "mcrn") else "soleprint"
+
+
+@app.get("/theme.css")
+def theme_css():
+    """Serve the theme contract plus every theme, concatenated."""
+    from fastapi.responses import Response
+
+    theme_dir = SPR_ROOT / "common" / "theme"
+    parts = []
+
+    tokens = theme_dir / "tokens.css"
+    if tokens.exists():
+        parts.append(tokens.read_text())
+
+    # Sorted so the response is byte-stable and cacheable; the theme files are
+    # scoped to [data-theme] selectors, so their order carries no meaning.
+    for sheet in sorted((theme_dir / "themes").glob("*.css")):
+        parts.append(f"\n/* ── {sheet.stem} ── */\n")
+        parts.append(sheet.read_text())
+
+    if not parts:
+        return Response(
+            content="/* theme not found — is common/theme/ present? */",
+            media_type="text/css",
+        )
+    return Response(content="".join(parts), media_type="text/css")
+
+
+@app.get("/theme.js")
+def theme_js():
+    """Serve the theme switcher."""
+    from fastapi.responses import Response
+
+    js_path = SPR_ROOT / "common" / "theme" / "theme.js"
+    if js_path.exists():
+        return Response(
+            content=js_path.read_text(), media_type="application/javascript"
+        )
+    return Response(
+        content="/* theme.js not found */", media_type="application/javascript"
+    )
+
+
+@app.get("/api/theme")
+def theme_config():
+    """The server-side default, for pages that render their own <html> tag."""
+    return {"theme": get_default_theme(), "themes": ["soleprint", "mcrn"]}
+
+
 @app.get("/sidebar.css")
 def sidebar_css():
     """Serve sidebar CSS for injection."""
diff --git a/soleprint/station/cabinets/README.md b/soleprint/station/cabinets/README.md
new file mode 100644
index 0000000..0cf0ac9
--- /dev/null
+++ b/soleprint/station/cabinets/README.md
@@ -0,0 +1,91 @@
+# Cabinets
+
+A cabinet is a **dependency container** a room can switch on: postgres, redis,
+airflow. The vocabulary already had the word — `execution.container` in every
+room's `config.json` is *"Cabinet — tool container"* — and until now nothing
+stood behind it.
+
+The problem it solves is that a generated artifact knows what it needs and had
+no way to say so. A shunt built from a client's spreadsheets can hold its rows
+in memory, but the moment you want them to survive a restart you need postgres,
+and wiring postgres in meant hand-editing a room's `docker-compose.yml` and then
+hand-editing the cluster too. A cabinet is that declaration, made once and read
+by both paths.
+
+```
+soleprint/station/cabinets/<name>/
+  cabinet.json    what it is, what it needs, what it exports
+  service.yml     the compose service, verbatim
+```
+
+## Turning one on
+
+Add `cfg/<room>/data/cabinets.json` — the same shape as its sibling `data/*.json`
+files:
+
+```json
+[
+  { "name": "postgres" },
+  { "name": "redis" },
+  { "name": "airflow", "env": { "AIRFLOW_ADMIN_PASSWORD": "change-me" } }
+]
+```
+
+Then build. `python build.py --cfg <room>` merges each cabinet's `service.yml`
+into the room's `docker-compose.yml` and appends its settings to `.env.example`:
+
+```bash
+python build.py --cfg sample
+cd gen/sample && docker compose up -d
+```
+
+**A service the room already declares wins.** `cfg/amar/docker-compose.yml`
+ships its own `db`; switching on the postgres cabinet will not overwrite it.
+Build says so when it skips one.
+
+## On a cluster
+
+`cabinet.json` names a `rig_addon`. Where the room runs on kind rather than
+compose, the same dependency installs as a rig addon of that name:
+
+```bash
+cd rig
+PROFILE=data make cluster up
+PROFILE=data make addons install
+```
+
+The two paths are deliberately separate — compose for a laptop, helm for a
+cluster — and `rig_addon` is the thread between them, so a room declares the
+dependency once either way.
+
+## Writing one
+
+`cabinet.json`:
+
+| Key | Purpose |
+| --- | --- |
+| `name` | must match the directory |
+| `title`, `description` | shown on the station index |
+| `image` | for the record; `service.yml` is what runs |
+| `service` | the key to merge under in `services:` (defaults to `name`) |
+| `env` | settings and defaults, written to `.env.example` |
+| `volumes` | named volumes to declare at the top level |
+| `depends_on` | other cabinets that must come with it |
+| `rig_addon` | the matching `rig/ctrl/addons/<name>.sh`, if there is one |
+| `ports` | host ports it wants, for the collision note in the docs |
+
+`service.yml` is a plain compose fragment — one top-level key, the service name:
+
+```yaml
+postgres:
+  image: postgres:16-alpine
+  environment:
+    POSTGRES_DB: ${POSTGRES_DB:-soleprint}
+  ...
+```
+
+Kept as YAML rather than generated from JSON so it reads like the compose file it
+becomes, and so anything compose supports is available without this tool
+learning about it first.
+
+Adding a cabinet is adding a directory. Nothing dispatches on the name.
diff --git a/soleprint/station/cabinets/airflow/cabinet.json b/soleprint/station/cabinets/airflow/cabinet.json
new file mode 100644
index 0000000..633e2c9
--- /dev/null
+++ b/soleprint/station/cabinets/airflow/cabinet.json
@@ -0,0 +1,22 @@
+{
+  "name": "airflow",
+  "title": "Apache Airflow",
+  "description": "Scheduled pipelines. DAGs live in the room, under dags/.",
+  "image": "apache/airflow:2.10.4",
+  "service": "airflow",
+  "rig_addon": "airflow",
+  "ports": [8080],
+  "volumes": ["airflow_logs"],
+  "depends_on": ["postgres", "redis"],
+  "env": {
+    "AIRFLOW_PORT": "8080",
+    "AIRFLOW_ADMIN_USER": "admin",
+    "AIRFLOW_ADMIN_PASSWORD": "change-me",
+    "AIRFLOW_DAGS_DIR": "./dags"
+  },
+  "notes": [
+    "Brings postgres and redis with it — Airflow needs a metadata database and a broker, and will not start without both.",
+    "LocalExecutor by default: one container, no separate worker. Switch to CeleryExecutor in service.yml when the room outgrows it.",
+    "8080 collides with almost everything. Set AIRFLOW_PORT in the room's .env."
+  ]
+}
diff --git a/soleprint/station/cabinets/airflow/service.yml b/soleprint/station/cabinets/airflow/service.yml
new file mode 100644
index 0000000..b0cebee
--- /dev/null
+++ b/soleprint/station/cabinets/airflow/service.yml
@@ -0,0 +1,37 @@
+# Airflow — scheduler and webserver in one container, on LocalExecutor.
+#
+# One container rather than the five the official compose file ships, because a
+# room switching this on wants pipelines, not a distributed deployment. The
+# metadata database is the postgres cabinet, so the two arrive together; moving
+# to CeleryExecutor is changing the executor here and adding a worker service.
+airflow:
+  image: apache/airflow:2.10.4
+  container_name: ${DEPLOYMENT_NAME:-soleprint}_airflow
+  depends_on:
+    postgres:
+      condition: service_healthy
+    redis:
+      condition: service_healthy
+  environment:
+    AIRFLOW__CORE__EXECUTOR: LocalExecutor
+    AIRFLOW__DATABASE__SQL_ALCHEMY_CONN: >-
+      postgresql+psycopg2://${POSTGRES_USER:-soleprint}:${POSTGRES_PASSWORD:-change-me}@postgres:5432/${POSTGRES_DB:-soleprint}
+    AIRFLOW__CELERY__BROKER_URL: redis://redis:6379/0
+    AIRFLOW__CORE__LOAD_EXAMPLES: "false"
+    # Without a fixed key, every restart invalidates stored connections.
+    AIRFLOW__CORE__FERNET_KEY: ${AIRFLOW_FERNET_KEY:-}
+    AIRFLOW__WEBSERVER__EXPOSE_CONFIG: "true"
+    _AIRFLOW_DB_MIGRATE: "true"
+    _AIRFLOW_WWW_USER_CREATE: "true"
+    _AIRFLOW_WWW_USER_USERNAME: ${AIRFLOW_ADMIN_USER:-admin}
+    _AIRFLOW_WWW_USER_PASSWORD: ${AIRFLOW_ADMIN_PASSWORD:-change-me}
+  volumes:
+    - ${AIRFLOW_DAGS_DIR:-./dags}:/opt/airflow/dags
+    - airflow_logs:/opt/airflow/logs
+  ports:
+    - "${AIRFLOW_PORT:-8080}:8080"
+  # `standalone` runs the migration, creates the admin user, and starts both
+  # the scheduler and the webserver — the whole first-boot sequence that the
+  # official compose file spreads across an init container and four services.
+  command: standalone
+  restart: unless-stopped
diff --git a/soleprint/station/cabinets/postgres/cabinet.json b/soleprint/station/cabinets/postgres/cabinet.json
new file mode 100644
index 0000000..0c3c61b
--- /dev/null
+++ b/soleprint/station/cabinets/postgres/cabinet.json
@@ -0,0 +1,20 @@
+{
+  "name": "postgres",
+  "title": "PostgreSQL",
+  "description": "Relational database. Backs rooms that need their data to outlive a restart.",
+  "image": "postgres:16-alpine",
+  "service": "postgres",
+  "rig_addon": "postgres",
+  "ports": [5432],
+  "volumes": ["pgdata"],
+  "env": {
+    "POSTGRES_DB": "soleprint",
+    "POSTGRES_USER": "soleprint",
+    "POSTGRES_PASSWORD": "change-me",
+    "POSTGRES_PORT": "5432"
+  },
+  "notes": [
+    "POSTGRES_PASSWORD is a placeholder. Set the real one in the room's .env, which is gitignored.",
+    "The connection string other services want is postgresql://${POSTGRES_USER}:${POSTGRES_PASSWORD}@postgres:5432/${POSTGRES_DB}"
+  ]
+}
diff --git a/soleprint/station/cabinets/postgres/service.yml b/soleprint/station/cabinets/postgres/service.yml
new file mode 100644
index 0000000..3979fd3
--- /dev/null
+++ b/soleprint/station/cabinets/postgres/service.yml
@@ -0,0 +1,24 @@
+# PostgreSQL — merged into a room's docker-compose.yml when the room asks for it.
+#
+# The healthcheck is not decoration: anything with `depends_on: condition:
+# service_healthy` waits on it, and without one a backend races the database on
+# every cold start and fails its first migration.
+postgres:
+  image: postgres:16-alpine
+  container_name: ${DEPLOYMENT_NAME:-soleprint}_postgres
+  environment:
+    POSTGRES_DB: ${POSTGRES_DB:-soleprint}
+    POSTGRES_USER: ${POSTGRES_USER:-soleprint}
+    POSTGRES_PASSWORD: ${POSTGRES_PASSWORD:-change-me}
+  volumes:
+    - pgdata:/var/lib/postgresql/data
+  ports:
+    # Bound on the host so psql and databrowse can reach it from outside the
+    # compose network. Override POSTGRES_PORT when 5432 is already taken.
+    - "${POSTGRES_PORT:-5432}:5432"
+  healthcheck:
+    test: ["CMD-SHELL", "pg_isready -U ${POSTGRES_USER:-soleprint} -d ${POSTGRES_DB:-soleprint}"]
+    interval: 10s
+    timeout: 5s
+    retries: 5
+  restart: unless-stopped
diff --git a/soleprint/station/cabinets/redis/cabinet.json b/soleprint/station/cabinets/redis/cabinet.json
new file mode 100644
index 0000000..548c01c
--- /dev/null
+++ b/soleprint/station/cabinets/redis/cabinet.json
@@ -0,0 +1,17 @@
+{
+  "name": "redis",
+  "title": "Redis",
+  "description": "In-memory store. Cache, and the broker Celery and Airflow run their queues on.",
+  "image": "redis:7-alpine",
+  "service": "redis",
+  "rig_addon": "redis",
+  "ports": [6379],
+  "volumes": ["redisdata"],
+  "env": {
+    "REDIS_PORT": "6379"
+  },
+  "notes": [
+    "The URL other services want is redis://redis:6379/0",
+    "Airflow depends on this one; switching airflow on brings it along."
+  ]
+}
diff --git a/soleprint/station/cabinets/redis/service.yml b/soleprint/station/cabinets/redis/service.yml
new file mode 100644
index 0000000..1a8d638
--- /dev/null
+++ b/soleprint/station/cabinets/redis/service.yml
@@ -0,0 +1,14 @@
+# Redis — cache, and the broker for anything queue-shaped in the room.
+redis:
+  image: redis:7-alpine
+  container_name: ${DEPLOYMENT_NAME:-soleprint}_redis
+  volumes:
+    - redisdata:/data
+  ports:
+    - "${REDIS_PORT:-6379}:6379"
+  healthcheck:
+    test: ["CMD", "redis-cli", "ping"]
+    interval: 10s
+    timeout: 5s
+    retries: 5
+  restart: unless-stopped
diff --git a/soleprint/station/index.html b/soleprint/station/index.html
index ae7a693..8af590b 100644
--- a/soleprint/station/index.html
+++ b/soleprint/station/index.html
@@ -1,5 +1,5 @@
 <!doctype html>
-<html lang="en">
+<html lang="en" data-theme="soleprint">
     <head>
         <meta charset="UTF-8" />
         <meta name="viewport" content="width=device-width, initial-scale=1.0" />
@@ -14,7 +14,7 @@
                 box-sizing: border-box;
             }
             html {
-                background: #0a0a0a;
+                background: var(--bg);
             }
             body {
                 font-family:
@@ -25,8 +25,8 @@
                 margin: 0 auto;
                 padding: 2rem 1rem;
                 line-height: 1.6;
-                color: #e5e5e5;
-                background: #1d4ed8;
+                color: var(--text);
+                background: var(--system-accent);
             }
             header {
                 display: flex;
@@ -51,7 +51,7 @@
                 padding-bottom: 2rem;
             }
             section {
-                background: #0a0a0a;
+                background: var(--bg);
                 padding: 1.5rem;
                 margin: 1.5rem 0;
                 border-radius: 12px;
@@ -59,23 +59,23 @@
             section h2 {
                 margin: 0 0 1rem 0;
                 font-size: 1.2rem;
-                color: #93c5fd;
+                color: var(--system-accent-text);
             }
             .composition {
-                background: #1a1a1a;
-                border: 2px solid #1d4ed8;
+                background: var(--surface);
+                border: 2px solid var(--system-accent);
                 padding: 1rem;
                 border-radius: 12px;
             }
             .composition h3 {
                 margin: 0 0 0.75rem 0;
                 font-size: 1.1rem;
-                color: #93c5fd;
+                color: var(--system-accent-text);
             }
             .composition > p {
                 margin: 0 0 1rem 0;
                 font-size: 0.9rem;
-                color: #a3a3a3;
+                color: var(--muted);
             }
             .components {
                 display: grid;
@@ -83,20 +83,20 @@
                 gap: 0.75rem;
             }
             .component {
-                background: #0a0a0a;
-                border: 1px solid #3f3f3f;
+                background: var(--bg);
+                border: 1px solid var(--border-strong);
                 padding: 0.75rem;
                 border-radius: 8px;
             }
             .component h4 {
                 margin: 0 0 0.25rem 0;
                 font-size: 0.95rem;
-                color: #93c5fd;
+                color: var(--system-accent-text);
             }
             .component p {
                 margin: 0;
                 font-size: 0.85rem;
-                color: #a3a3a3;
+                color: var(--muted);
             }
             .tables {
                 list-style: none;
@@ -105,7 +105,7 @@
             }
             .tables li {
                 padding: 0.75rem 0;
-                border-bottom: 1px solid #3f3f3f;
+                border-bottom: 1px solid var(--border-strong);
                 display: flex;
                 justify-content: space-between;
                 align-items: center;
@@ -116,32 +116,32 @@
             .tables .name {
                 font-weight: 500;
                 text-decoration: none;
-                color: #e5e5e5;
+                color: var(--text);
             }
             .tables a.name:hover {
-                color: #93c5fd;
+                color: var(--system-accent-text);
             }
             .status {
                 font-size: 0.75rem;
                 padding: 0.2rem 0.5rem;
                 border-radius: 4px;
                 text-transform: uppercase;
-                background: #2a2a2a;
-                color: #a3a3a3;
+                background: var(--border);
+                color: var(--muted);
             }
             .health {
                 display: inline-block;
                 margin-top: 1rem;
                 padding: 0.5rem 1rem;
-                background: #1a1a1a;
-                border: 1px solid #3f3f3f;
+                background: var(--surface);
+                border: 1px solid var(--border-strong);
                 border-radius: 4px;
                 font-family: monospace;
-                color: #93c5fd;
+                color: var(--system-accent-text);
                 text-decoration: none;
             }
             .health:hover {
-                background: #2a2a2a;
+                background: var(--border);
             }
             footer {
                 margin-top: 3rem;
@@ -157,7 +157,12 @@
                 opacity: 0.5;
             }
         </style>
-    </head>
+      <link rel="stylesheet" href="/theme.css">
+  <style>
+    /* Station keeps its own colour under every theme. */
+    :root { --system-accent: #1d4ed8; --system-accent-text: #93c5fd; }
+  </style>
+</head>
     <body>
         <header style="position: relative">
             <!-- Control station / monitor -->
@@ -217,6 +222,20 @@
             </ul>
         </section>
 
+        <section>
+            <h2>{{ (components.container.plural or 'cabinets')|title }}</h2>
+            <ul class="tables">
+                {% for cabinet in cabinets %}
+                <li>
+                    <span class="name">{{ cabinet.title }}</span
+                    ><span class="status">{{ cabinet.status }}</span>
+                </li>
+                {% else %}
+                <li><span class="name">--</span></li>
+                {% endfor %}
+            </ul>
+        </section>
+
         <section>
             <h2>{{ (components.watcher.plural or 'monitors')|title }}</h2>
             <ul class="tables">
@@ -263,5 +282,6 @@
             {% if soleprint_url %}<a href="{{ soleprint_url }}">← Soleprint</a
             >{% else %}<span class="disabled">← Soleprint</span>{% endif %}
         </footer>
-    </body>
+      <script src="/theme.js" defer></script>
+</body>
 </html>
diff --git a/soleprint/station/tools/datagen/templates/index.html b/soleprint/station/tools/datagen/templates/index.html
index 0640694..0c9057e 100644
--- a/soleprint/station/tools/datagen/templates/index.html
+++ b/soleprint/station/tools/datagen/templates/index.html
@@ -1,27 +1,19 @@
 <!DOCTYPE html>
-<html lang="en">
+<html lang="en" data-theme="soleprint">
 <head>
   <meta charset="UTF-8">
   <meta name="viewport" content="width=device-width, initial-scale=1.0">
   <title>datagen — Test Data Generator</title>
+  <!-- Palette, fonts and the theme switcher. The :root block that used to sit
+       here was one of eight copies that had already drifted apart. -->
+  <link rel="stylesheet" href="/theme.css">
   <style>
-    :root {
-      --bg: #0a0a0a;
-      --surface: #1a1a1a;
-      --border: #333;
-      --text: #e5e5e5;
-      --muted: #a3a3a3;
-      --dim: #666;
-      --amber: #d4a574;
-      --amber-dim: #b8956a;
-    }
-
     * { box-sizing: border-box; margin: 0; padding: 0; }
 
     body {
       background: var(--bg);
       color: var(--text);
-      font-family: system-ui, -apple-system, sans-serif;
+      font-family: var(--font-ui);
       font-size: 13px;
       height: 100vh;
       display: flex;
@@ -493,5 +485,6 @@ document.addEventListener('keydown', e => {
 
 init();
 </script>
+  <script src="/theme.js" defer></script>
 </body>
 </html>
diff --git a/soleprint/station/tools/graphgen/templates/index.html b/soleprint/station/tools/graphgen/templates/index.html
index c3edb0e..9389014 100644
--- a/soleprint/station/tools/graphgen/templates/index.html
+++ b/soleprint/station/tools/graphgen/templates/index.html
@@ -1,27 +1,18 @@
 <!DOCTYPE html>
-<html lang="en">
+<html lang="en" data-theme="soleprint">
 <head>
   <meta charset="UTF-8">
   <meta name="viewport" content="width=device-width, initial-scale=1.0">
   <title>graphgen — Schema Explorer</title>
+  <!-- Palette, fonts and the theme switcher — see common/theme/. -->
+  <link rel="stylesheet" href="/theme.css">
   <style>
-    :root {
-      --bg: #0a0a0a;
-      --surface: #1a1a1a;
-      --border: #333;
-      --text: #e5e5e5;
-      --muted: #a3a3a3;
-      --dim: #666;
-      --amber: #d4a574;
-      --amber-dim: #b8956a;
-    }
-
     * { box-sizing: border-box; margin: 0; padding: 0; }
 
     body {
       background: var(--bg);
       color: var(--text);
-      font-family: system-ui, -apple-system, sans-serif;
+      font-family: var(--font-ui);
       font-size: 13px;
       overflow: hidden;
       height: 100vh;
@@ -725,5 +716,6 @@ function svgEl(tag) {
 applyViewport();
 init();
 </script>
+  <script src="/theme.js" defer></script>
 </body>
 </html>
diff --git a/soleprint/station/tools/modelgen/__main__.py b/soleprint/station/tools/modelgen/__main__.py
index 7eff8bf..2ae435a 100644
--- a/soleprint/station/tools/modelgen/__main__.py
+++ b/soleprint/station/tools/modelgen/__main__.py
@@ -4,9 +4,12 @@ Modelgen - Generic Model Generation Tool
 Generates typed models from various sources to various formats.
 
 Input sources:
-- from-config: Configuration files (soleprint config.json style)
-- from-schema: Python dataclasses in schema/ folder
-- extract: Existing codebases (Django, SQLAlchemy, Prisma)
+- from-config:  Configuration files (soleprint config.json style)
+- from-schema:  Python dataclasses in schema/ folder
+- extract:      Existing codebases (Django, SQLAlchemy)
+- from-db:      A live database, any SQLAlchemy dialect
+- from-openapi: An OpenAPI 3.x / Swagger 2.0 document
+- from-tabular: A directory of CSV/TSV/ODS spreadsheets
 
 Output formats:
 - pydantic: Pydantic BaseModel classes
@@ -14,12 +17,16 @@ Output formats:
 - typescript: TypeScript interfaces
 - protobuf: Protocol Buffer definitions
 - prisma: Prisma schema
+- schema: graphgen-compatible schema.json
+- datagen: BaseDataGenerator subclass for station's datagen tool
 
 Usage:
     python -m soleprint.station.tools.modelgen --help
     python -m soleprint.station.tools.modelgen from-config -c config.json -o models.py
     python -m soleprint.station.tools.modelgen from-schema -o models/ --targets pydantic,typescript
     python -m soleprint.station.tools.modelgen extract --source /path/to/django --targets pydantic
+    python -m soleprint.station.tools.modelgen from-openapi -s api.yaml -o out/ -t pydantic,schema
+    python -m soleprint.station.tools.modelgen from-tabular -s ./sheets -o out/ -t pydantic,datagen
     python -m soleprint.station.tools.modelgen generate --config schema/modelgen.json
 """
 
@@ -225,6 +232,88 @@ def cmd_from_db(args):
     print("Done!")
 
 
+def _emit(payload, targets_arg: str, output: str) -> None:
+    """Run one extraction result through every requested target.
+
+    The three older commands each carry their own copy of this loop; the two
+    below share it, because they also have to pass datasets through and a
+    fourth copy would be a fourth place to keep in step.
+    """
+    targets = [t.strip() for t in targets_arg.split(",") if t.strip()]
+    output_dir = Path(output)
+
+    for target in targets:
+        if target not in GENERATORS:
+            print(f"Warning: Unknown target '{target}', skipping", file=sys.stderr)
+            continue
+
+        generator = GENERATORS[target]()
+        ext = generator.file_extension()
+
+        # Determine output filename (use target name to avoid overwrites)
+        if len(targets) == 1 and output.endswith(ext):
+            output_file = output_dir
+        else:
+            output_file = output_dir / f"models_{target}{ext}"
+
+        print(f"Generating {target} to: {output_file}")
+        generator.generate(payload, output_file)
+
+    print("Done!")
+
+
+def cmd_from_openapi(args):
+    """Generate models from an OpenAPI 3.x / Swagger 2.0 document."""
+    from .loader.extract.openapi import OpenAPIExtractor
+
+    spec_path = Path(args.spec)
+    if not spec_path.exists():
+        print(f"Error: Spec not found: {spec_path}", file=sys.stderr)
+        sys.exit(1)
+
+    extractor = OpenAPIExtractor(spec_path)
+    print(f"Reading spec: {spec_path}")
+    try:
+        models, enums = extractor.extract()
+    except (RuntimeError, ValueError) as e:
+        print(f"Error: {e}", file=sys.stderr)
+        sys.exit(1)
+
+    endpoints = extractor.endpoints()
+    print(
+        f"Extracted {len(models)} models, {len(enums)} enums, "
+        f"{len(endpoints)} endpoints"
+    )
+
+    _emit((models, enums), args.targets, args.output)
+
+
+def cmd_from_tabular(args):
+    """Generate models from a directory of CSV/TSV/ODS spreadsheets."""
+    from .loader.extract.tabular import TabularExtractor
+
+    source_path = Path(args.source)
+    if not source_path.exists():
+        print(f"Error: Source not found: {source_path}", file=sys.stderr)
+        sys.exit(1)
+
+    extractor = TabularExtractor(source_path)
+    print(f"Reading sheets: {source_path}")
+    try:
+        models, enums = extractor.extract()
+    except ValueError as e:
+        print(f"Error: {e}", file=sys.stderr)
+        sys.exit(1)
+
+    datasets = extractor.datasets()
+    rows = sum(len(d.rows) for d in datasets)
+    print(f"Extracted {len(models)} models, {rows} rows")
+
+    # Datasets ride along as a third element: the datagen target seeds from
+    # them, and every other target ignores the extra slot.
+    _emit((models, enums, datasets), args.targets, args.output)
+
+
 def cmd_generate(args):
     """Generate all targets from a JSON config file."""
     import json
@@ -430,6 +519,63 @@ def main():
     )
     db_parser.set_defaults(func=cmd_from_db)
 
+    # from-openapi command (service contract -> models)
+    openapi_parser = subparsers.add_parser(
+        "from-openapi",
+        help="Generate models from an OpenAPI 3.x / Swagger 2.0 document",
+    )
+    openapi_parser.add_argument(
+        "--spec",
+        "-s",
+        type=str,
+        required=True,
+        help="Path to the spec (.json, .yaml or .yml; YAML needs PyYAML)",
+    )
+    openapi_parser.add_argument(
+        "--output",
+        "-o",
+        type=str,
+        required=True,
+        help="Output path (file or directory)",
+    )
+    openapi_parser.add_argument(
+        "--targets",
+        "-t",
+        type=str,
+        default="pydantic",
+        help=f"Comma-separated output targets ({formats_str})",
+    )
+    openapi_parser.set_defaults(func=cmd_from_openapi)
+
+    # from-tabular command (spreadsheets -> models + rows)
+    tabular_parser = subparsers.add_parser(
+        "from-tabular",
+        help="Generate models from a directory of CSV/TSV/ODS spreadsheets",
+    )
+    tabular_parser.add_argument(
+        "--source",
+        "-s",
+        type=str,
+        required=True,
+        help="Directory of sheets (or a single .csv/.tsv/.ods file)",
+    )
+    tabular_parser.add_argument(
+        "--output",
+        "-o",
+        type=str,
+        required=True,
+        help="Output path (file or directory)",
+    )
+    tabular_parser.add_argument(
+        "--targets",
+        "-t",
+        type=str,
+        default="pydantic",
+        help=f"Comma-separated output targets ({formats_str}). "
+        "The datagen target seeds from the imported rows.",
+    )
+    tabular_parser.set_defaults(func=cmd_from_tabular)
+
     # generate command (config-driven multi-target)
     gen_parser = subparsers.add_parser(
         "generate",
diff --git a/soleprint/station/tools/modelgen/generator/__init__.py b/soleprint/station/tools/modelgen/generator/__init__.py
index 9a83ac5..f63168d 100644
--- a/soleprint/station/tools/modelgen/generator/__init__.py
+++ b/soleprint/station/tools/modelgen/generator/__init__.py
@@ -8,11 +8,13 @@ Supported generators:
 - ProtobufGenerator: Protocol Buffer definitions
 - PrismaGenerator: Prisma schema
 - StrawberryGenerator: Strawberry type/input/enum classes
+- DatagenGenerator: BaseDataGenerator subclass for station's datagen tool
 """
 
 from typing import Dict, Type
 
 from .base import BaseGenerator
+from .datagen import DatagenGenerator
 from .django import DjangoGenerator
 from .jsonschema import JsonSchemaGenerator
 from .prisma import PrismaGenerator
@@ -35,10 +37,12 @@ GENERATORS: Dict[str, Type[BaseGenerator]] = {
     "strawberry": StrawberryGenerator,
     "schema": JsonSchemaGenerator,
     "jsonschema": JsonSchemaGenerator,  # Alias
+    "datagen": DatagenGenerator,
 }
 
 __all__ = [
     "BaseGenerator",
+    "DatagenGenerator",
     "PydanticGenerator",
     "DjangoGenerator",
     "StrawberryGenerator",
diff --git a/soleprint/station/tools/modelgen/generator/datagen.py b/soleprint/station/tools/modelgen/generator/datagen.py
new file mode 100644
index 0000000..f7d7e27
--- /dev/null
+++ b/soleprint/station/tools/modelgen/generator/datagen.py
@@ -0,0 +1,399 @@
+"""
+Datagen Generator
+
+Emits a BaseDataGenerator subclass — the bridge between modelgen (which knows
+the shapes) and datagen (which hands out instances of them).
+
+The contract it targets is datagen/base.py: a method per model, named the way
+`generate()` looks it up (`model.lower()`), plus a `schema()` override in the
+graphgen-compatible format so the result also renders in graphgen with no extra
+work.
+
+Two modes, chosen by what the loader had:
+
+  - No rows      → every field is synthesised from its type.
+  - Rows present → the generated class samples depot/data.json, so a shunt
+                   built from a spreadsheet answers with the real values and
+                   only invents where it must.
+
+Synthesis uses random/uuid/datetime from the standard library rather than
+faker, which is not a dependency of this repo despite what datagen's README
+examples suggest.
+"""
+
+import json
+from enum import Enum
+from pathlib import Path
+from pprint import pformat
+from typing import Any, Dict, List, Optional
+
+from ..helpers import unwrap_optional
+from ..loader.schema import ModelDefinition
+from .base import BaseGenerator
+
+# Field-name heuristics. A column called `email` deserves something that looks
+# like an email — a mock whose every string is "string_4" is hard to read and
+# hard to demo.
+_NAME_HINTS = (
+    ("email", '"user{n}@example.com".format(n=random.randint(1, 999))'),
+    ("phone", '"+1-555-{n:04d}".format(n=random.randint(0, 9999))'),
+    ("url", '"https://example.com/{n}".format(n=random.randint(1, 999))'),
+    ("slug", 'random.choice(_WORDS) + "-" + str(random.randint(1, 99))'),
+    ("first_name", "random.choice(_FIRST_NAMES)"),
+    ("last_name", "random.choice(_LAST_NAMES)"),
+    ("name", 'random.choice(_FIRST_NAMES) + " " + random.choice(_LAST_NAMES)'),
+    ("title", 'random.choice(_WORDS).title() + " " + random.choice(_WORDS)'),
+    ("description", '" ".join(random.choices(_WORDS, k=8))'),
+    ("address", '"{n} ".format(n=random.randint(1, 9999)) + random.choice(_WORDS).title() + " St"'),
+    ("city", "random.choice(_CITIES)"),
+    ("country", "random.choice(_COUNTRIES)"),
+    ("currency", 'random.choice(["USD", "EUR", "ARS", "GBP"])'),
+    ("status", 'random.choice(["active", "pending", "closed"])'),
+    ("code", '"".join(random.choices("ABCDEFGHJKLMNPQRSTUVWXYZ0123456789", k=6))'),
+    ("token", "uuid.uuid4().hex"),
+    ("color", '"#{n:06x}".format(n=random.randint(0, 0xFFFFFF))'),
+)
+
+_HEADER_HELPERS = '''
+_WORDS = [
+    "alpha", "bravo", "cobalt", "delta", "ember", "falcon", "granite", "harbor",
+    "indigo", "juniper", "kestrel", "lumen", "meridian", "nimbus", "onyx",
+]
+_FIRST_NAMES = ["Ada", "Bruno", "Camila", "Diego", "Elena", "Facundo", "Gabriela", "Hugo"]
+_LAST_NAMES = ["Alvarez", "Bianchi", "Castro", "Duarte", "Esposito", "Ferrari", "Gomez"]
+_CITIES = ["Buenos Aires", "Rosario", "Cordoba", "Montevideo", "Santiago", "Lisbon"]
+_COUNTRIES = ["AR", "UY", "CL", "BR", "PT", "ES"]
+'''
+
+_FALLBACK_BASE = '''
+    # Standalone fallback: a generated generator has to keep working inside a
+    # shunt, which runs as its own process with no soleprint on the path. This
+    # mirrors station/tools/datagen/base.py.
+    class BaseDataGenerator:  # type: ignore[no-redef]
+        """Minimal stand-in for station.tools.datagen.base.BaseDataGenerator."""
+
+        _RESERVED = frozenset({"generate", "available_models", "schema"})
+
+        def generate(self, model: str, count: int = 1, **kwargs) -> list:
+            method = getattr(self, model.lower(), None)
+            if method is None or not callable(method):
+                raise ValueError(
+                    f"No generator for '{model}'. Available: {self.available_models()}"
+                )
+            return [method(**kwargs) for _ in range(count)]
+
+        def available_models(self) -> list:
+            return sorted(
+                name for name in dir(self)
+                if not name.startswith("_")
+                and name not in self._RESERVED
+                and callable(getattr(self, name))
+            )
+
+        def schema(self):
+            return None
+'''
+
+
+class DatagenGenerator(BaseGenerator):
+    """Generates a BaseDataGenerator subclass from model definitions."""
+
+    def __init__(
+        self,
+        name_map: Optional[Dict[str, str]] = None,
+        class_name: Optional[str] = None,
+        depot: str = "depot/data.json",
+    ):
+        super().__init__(name_map)
+        self.class_name = class_name
+        # Relative to the generated file, so the shunt directory stays movable.
+        self.depot = depot
+
+    def file_extension(self) -> str:
+        return ".py"
+
+    def generate(self, models, output_path: Path) -> None:
+        model_defs, _enums, datasets = self._unpack(models)
+
+        output_path = Path(output_path)
+        if output_path.suffix != ".py":
+            output_path = output_path / "generated_datagen.py"
+        output_path.parent.mkdir(parents=True, exist_ok=True)
+
+        class_name = self.class_name or self._derive_class_name(output_path)
+        seeded = {d.model for d in datasets if d.rows}
+        model_names = {self.map_name(m.name) for m in model_defs}
+
+        lines = self._header(class_name, bool(seeded))
+        for model_def in model_defs:
+            lines.extend(self._model_method(model_def, model_names, seeded))
+            lines.append("")
+
+        lines.extend(self._schema_method(model_defs, model_names))
+        lines.append("")
+        lines.extend(self._helpers(bool(seeded)))
+
+        output_path.write_text("\n".join(lines))
+
+    # ── input handling ─────────────────────────────────────────────────────
+
+    @staticmethod
+    def _unpack(models) -> tuple:
+        """Accept the shapes the other generators accept, plus datasets."""
+        if isinstance(models, tuple):
+            model_defs = list(models[0])
+            enum_defs = list(models[1]) if len(models) > 1 else []
+            datasets = list(models[2]) if len(models) > 2 else []
+            return model_defs, enum_defs, datasets
+        if hasattr(models, "models"):
+            # SchemaLoader
+            model_defs = list(models.models) + list(getattr(models, "api_models", []))
+            return model_defs, list(getattr(models, "enums", [])), []
+        if isinstance(models, list):
+            return list(models), [], []
+        raise ValueError(f"Unsupported input type: {type(models)}")
+
+    @staticmethod
+    def _derive_class_name(output_path: Path) -> str:
+        stem = output_path.stem.replace("datagen_", "").replace("_datagen", "")
+        parts = [p for p in stem.replace("-", "_").split("_") if p]
+        base = "".join(p[:1].upper() + p[1:] for p in parts) or "Generated"
+        return f"{base}Generator"
+
+    # ── emission ───────────────────────────────────────────────────────────
+
+    def _header(self, class_name: str, seeded: bool) -> List[str]:
+        lines = [
+            '"""',
+            "Data generator - GENERATED FILE",
+            "",
+            "Do not edit directly. Regenerate using modelgen (target: datagen).",
+            '"""',
+            "",
+            "import json",
+            "import random",
+            "import uuid",
+            "from datetime import datetime, timedelta, timezone",
+            "from pathlib import Path",
+            "",
+            "try:",
+            "    from station.tools.datagen.base import BaseDataGenerator",
+            "except ImportError:  # pragma: no cover - standalone use",
+            _FALLBACK_BASE.strip("\n"),
+            "",
+            _HEADER_HELPERS.strip("\n"),
+            "",
+            "",
+            f"class {class_name}(BaseDataGenerator):",
+            '    """Generated from a modelgen schema."""',
+            "",
+        ]
+        if seeded:
+            lines.extend([
+                f'    _DEPOT = Path(__file__).parent / "{self.depot}"',
+                "",
+                "    def __init__(self):",
+                "        self._seed = {}",
+                "        if self._DEPOT.exists():",
+                "            try:",
+                "                self._seed = json.loads(self._DEPOT.read_text())",
+                "            except (OSError, ValueError):",
+                "                self._seed = {}",
+                "",
+            ])
+        return lines
+
+    def _model_method(
+        self, model_def: ModelDefinition, model_names: set, seeded: set
+    ) -> List[str]:
+        mapped = self.map_name(model_def.name)
+        doc = (model_def.docstring or mapped).strip().splitlines()[0]
+
+        lines = [
+            f"    def {mapped.lower()}(self, **kwargs) -> dict:",
+            f'        """{doc}"""',
+        ]
+
+        if model_def.name in seeded:
+            # Real rows first; synthesis is the fallback for when the depot is
+            # missing or a caller asked for more rows than were imported.
+            lines.append(f'        record = self._sample("{model_def.name}")')
+            lines.append("        if record is None:")
+            indent = "            "
+        else:
+            indent = "        "
+
+        if model_def.fields:
+            lines.append(f"{indent}record = {{")
+            for field in model_def.fields:
+                value = self._value(field, model_names)
+                lines.append(f'{indent}    "{field.name}": {value},')
+            lines.append(f"{indent}}}")
+        else:
+            lines.append(f"{indent}record = {{}}")
+
+        lines.append("        record.update(kwargs)")
+        lines.append("        return record")
+        return lines
+
+    def _value(self, field: Any, model_names: set) -> str:
+        base, _ = unwrap_optional(field.type_hint)
+        name = field.name.lower()
+
+        if getattr(field, "primary_key", False):
+            if base in (int, "bigint"):
+                return "self._next_id()"
+            return "str(uuid.uuid4())"
+
+        fk = getattr(field, "foreign_key", None)
+        if fk:
+            target = self.map_name(fk)
+            # How a relation is carried depends on the shape it was found in.
+            # A `customer_id` column holds a key; a `category` property in a
+            # spec holds the object itself, and answering that one with a key
+            # would be the wrong shape, not merely a dull value.
+            if base == "dict":
+                return f'self._nested("{target}")'
+            if base == "list":
+                return f'self._nested_list("{target}")'
+            if base in (int, "bigint"):
+                # A plausible existing key, not a fresh one: a foreign key that
+                # never matches anything makes the mock useless for joins.
+                return "random.randint(1, 100)"
+            return "str(uuid.uuid4())"
+
+        if isinstance(base, type) and issubclass(base, Enum):
+            values = json.dumps([m.value for m in base])
+            return f"random.choice({values})"
+
+        if base is bool:
+            return "random.choice([True, False])"
+        if base in (int, "bigint"):
+            return "random.randint(1, 10000)"
+        if base is float:
+            return "round(random.uniform(1, 10000), 2)"
+        if base == "UUID":
+            return "str(uuid.uuid4())"
+        if base == "datetime":
+            return "self._recent()"
+        if base == "dict":
+            return "{}"
+        if base == "list":
+            return "[]"
+        if base == "bytes":
+            return '""'
+
+        for hint, expression in _NAME_HINTS:
+            if hint in name:
+                return expression
+
+        return 'random.choice(_WORDS) + "-" + str(random.randint(1, 999))'
+
+    def _schema_method(
+        self, model_defs: List[ModelDefinition], model_names: set
+    ) -> List[str]:
+        schema: Dict[str, Any] = {"models": {}}
+        for model_def in model_defs:
+            mapped = self.map_name(model_def.name)
+            entry: Dict[str, Any] = {}
+            if model_def.docstring:
+                entry["doc"] = model_def.docstring.strip().splitlines()[0]
+            fields: Dict[str, Any] = {}
+            for field in model_def.fields:
+                fields[field.name] = self._schema_field(field, model_names)
+            entry["fields"] = fields
+            schema["models"][mapped] = entry
+
+        # pformat, not json.dumps: the result is spliced into a source file, so
+        # it has to be a Python literal. Post-processing JSON with string
+        # replacement would rewrite "true" inside a docstring too.
+        body = pformat(schema, indent=4, width=88, sort_dicts=False)
+        indented = "\n".join(f"        {line}" for line in body.splitlines())
+
+        return [
+            "    def schema(self) -> dict:",
+            '        """Graphgen-compatible schema — surfaced at /tools/datagen/api/schema."""',
+            f"        return {indented.lstrip()}",
+        ]
+
+    def _schema_field(self, field: Any, model_names: set) -> Dict[str, Any]:
+        base, is_optional = unwrap_optional(field.type_hint)
+        fk = getattr(field, "foreign_key", None)
+
+        if fk:
+            relation = "M2M" if getattr(field, "many", False) else "FK"
+            type_value = f"{relation}:{self.map_name(fk)}"
+        elif isinstance(base, type) and issubclass(base, Enum):
+            type_value = base.__name__
+        elif isinstance(base, str):
+            type_value = base
+        elif hasattr(base, "__name__"):
+            type_value = base.__name__
+        else:
+            type_value = "Any"
+
+        out: Dict[str, Any] = {
+            "type": type_value,
+            "nullable": bool(getattr(field, "optional", False) or is_optional),
+        }
+        if getattr(field, "primary_key", False):
+            out["pk"] = True
+        if getattr(field, "unique", False):
+            out["unique"] = True
+        return out
+
+    @staticmethod
+    def _helpers(seeded: bool) -> List[str]:
+        lines = [
+            "    # ── helpers ────────────────────────────────────────────────",
+            "",
+            "    _counter = 0",
+            "",
+            "    def _next_id(self) -> int:",
+            '        """Monotonic ids, so generated relations can be joined."""',
+            "        type(self)._counter += 1",
+            "        return type(self)._counter",
+            "",
+            "    @staticmethod",
+            "    def _recent() -> str:",
+            '        """An ISO timestamp within the last 90 days."""',
+            "        moment = datetime.now(timezone.utc) - timedelta(",
+            "            days=random.randint(0, 90), seconds=random.randint(0, 86399)",
+            "        )",
+            "        return moment.isoformat()",
+            "",
+            "    # Nesting is capped rather than followed: schemas refer to each",
+            "    # other in cycles, and an uncapped expansion recurses forever.",
+            "    _depth = 0",
+            "    _MAX_DEPTH = 2",
+            "",
+            "    def _nested(self, model: str):",
+            '        """One related object, or None once the depth cap is reached."""',
+            "        if type(self)._depth >= self._MAX_DEPTH:",
+            "            return None",
+            "        method = getattr(self, model.lower(), None)",
+            "        if not callable(method):",
+            "            return None",
+            "        type(self)._depth += 1",
+            "        try:",
+            "            return method()",
+            "        finally:",
+            "            type(self)._depth -= 1",
+            "",
+            "    def _nested_list(self, model: str, count: int = 2) -> list:",
+            '        """A short list of related objects."""',
+            "        items = [self._nested(model) for _ in range(count)]",
+            "        return [item for item in items if item is not None]",
+        ]
+        if seeded:
+            lines.extend([
+                "",
+                "    def _sample(self, model: str):",
+                '        """A copy of a real imported row, or None if there are none."""',
+                "        rows = self._seed.get(model) or []",
+                "        if not rows:",
+                "            return None",
+                "        return dict(random.choice(rows))",
+            ])
+        lines.append("")
+        return lines
diff --git a/soleprint/station/tools/modelgen/generator/jsonschema.py b/soleprint/station/tools/modelgen/generator/jsonschema.py
index 6069dc2..050b369 100644
--- a/soleprint/station/tools/modelgen/generator/jsonschema.py
+++ b/soleprint/station/tools/modelgen/generator/jsonschema.py
@@ -84,7 +84,8 @@ class JsonSchemaGenerator(BaseGenerator):
 
         # Resolve the relationship-aware type string graphgen expects.
         if fk_target:
-            type_value = f"FK:{self.map_name(fk_target)}"
+            relation = "M2M" if getattr(field, "many", False) else "FK"
+            type_value = f"{relation}:{self.map_name(fk_target)}"
         elif type_str in model_names:
             type_value = f"FK:{type_str}"
         elif type_str == "M2M":
diff --git a/soleprint/station/tools/modelgen/generator/protobuf.py b/soleprint/station/tools/modelgen/generator/protobuf.py
index 10a3a38..a037df4 100644
--- a/soleprint/station/tools/modelgen/generator/protobuf.py
+++ b/soleprint/station/tools/modelgen/generator/protobuf.py
@@ -27,8 +27,9 @@ class ProtobufGenerator(BaseGenerator):
         if hasattr(models, "grpc_messages"):
             # SchemaLoader with gRPC definitions
             content = self._generate_from_loader(models)
-        elif isinstance(models, tuple) and len(models) >= 3:
-            # (messages, service_def) tuple
+        elif isinstance(models, tuple) and len(models) >= 2:
+            # (models, enums, ...) tuple — same first two slots as every other
+            # generator; extra slots (datasets) belong to targets that use them.
             content = self._generate_from_definitions(models[0], models[1])
         elif isinstance(models, list):
             # List of dataclasses (MPR style)
diff --git a/soleprint/station/tools/modelgen/loader/__init__.py b/soleprint/station/tools/modelgen/loader/__init__.py
index c99d794..9c2e27d 100644
--- a/soleprint/station/tools/modelgen/loader/__init__.py
+++ b/soleprint/station/tools/modelgen/loader/__init__.py
@@ -8,8 +8,16 @@ Supported loaders:
 """
 
 from .config import ConfigLoader, load_config
-from .extract import EXTRACTORS, BaseExtractor, DjangoExtractor
+from .extract import (
+    EXTRACTORS,
+    BaseExtractor,
+    DjangoExtractor,
+    OpenAPIExtractor,
+    TabularExtractor,
+)
 from .schema import (
+    DatasetDefinition,
+    EndpointDefinition,
     EnumDefinition,
     FieldDefinition,
     GrpcServiceDefinition,
@@ -30,8 +38,12 @@ __all__ = [
     "FieldDefinition",
     "EnumDefinition",
     "GrpcServiceDefinition",
+    "EndpointDefinition",
+    "DatasetDefinition",
     # Extractors
     "BaseExtractor",
     "DjangoExtractor",
+    "OpenAPIExtractor",
+    "TabularExtractor",
     "EXTRACTORS",
 ]
diff --git a/soleprint/station/tools/modelgen/loader/extract/__init__.py b/soleprint/station/tools/modelgen/loader/extract/__init__.py
index 08a7bde..b3badf0 100644
--- a/soleprint/station/tools/modelgen/loader/extract/__init__.py
+++ b/soleprint/station/tools/modelgen/loader/extract/__init__.py
@@ -1,29 +1,41 @@
 """
 Extractors - Extract model definitions from existing codebases.
 
-Supported frameworks:
+Supported sources:
 - Django: Extract from Django ORM models
-- SQLAlchemy: Extract from SQLAlchemy models (planned)
-- Prisma: Extract from Prisma schema (planned)
+- SQLAlchemy: Extract from SQLAlchemy models
+- OpenAPI: Extract from an OpenAPI 3.x / Swagger 2.0 document
+- Tabular: Extract from a directory of CSV/TSV/ODS spreadsheets
 """
 
 from typing import Dict, Type
 
 from .base import BaseExtractor
 from .django import DjangoExtractor
+from .openapi import OpenAPIExtractor
 from .sqlalchemy_models import SqlAlchemyExtractor
+from .tabular import TabularExtractor
 
-# Registry of code-source extractors (auto-detectable via detect()).
+# Registry of source extractors (auto-detectable via detect()).
+#
+# Ordering matters for `--framework auto`: detection runs in insertion order and
+# stops at the first match, so the two that inspect a *file* come after the two
+# that inspect a *source tree* and cannot be confused with them.
+#
 # Note: live-database introspection lives in database.py (DatabaseExtractor),
 # invoked explicitly via the `from-db` command since it takes a URL, not a path.
 EXTRACTORS: Dict[str, Type[BaseExtractor]] = {
     "django": DjangoExtractor,
     "sqlalchemy": SqlAlchemyExtractor,
+    "openapi": OpenAPIExtractor,
+    "tabular": TabularExtractor,
 }
 
 __all__ = [
     "BaseExtractor",
     "DjangoExtractor",
     "SqlAlchemyExtractor",
+    "OpenAPIExtractor",
+    "TabularExtractor",
     "EXTRACTORS",
 ]
diff --git a/soleprint/station/tools/modelgen/loader/extract/openapi.py b/soleprint/station/tools/modelgen/loader/extract/openapi.py
new file mode 100644
index 0000000..bb20870
--- /dev/null
+++ b/soleprint/station/tools/modelgen/loader/extract/openapi.py
@@ -0,0 +1,440 @@
+"""
+OpenAPI Extractor
+
+Reads an OpenAPI 3.x or Swagger 2.0 document and produces modelgen's IR.
+
+One parse yields two products:
+
+    extractor = OpenAPIExtractor("api.yaml")
+    models, enums = extractor.extract()     # the shapes  (BaseExtractor contract)
+    endpoints     = extractor.endpoints()   # the routes  (what shuntgen consumes)
+
+Only the first is part of the BaseExtractor contract; a spec is the one input
+that describes calls as well as shapes, so endpoints() is an addition rather
+than a widening of the ABC.
+
+Referenced schemas become foreign_key metadata rather than nested types, which
+is the same call DatabaseExtractor makes (see database.py) and for the same
+reason: it keeps every generator emitting valid code, and graphgen still draws
+the edge. Enums are materialised as real Enum classes so the existing
+PYDANTIC_RESOLVERS/TS_RESOLVERS "enum" branch resolves them by name.
+
+YAML is optional. JSON specs parse with the stdlib alone — which is what keeps
+modelgen installable with no dependencies — and a .yaml spec needs PyYAML.
+"""
+
+import json
+import re
+from enum import Enum
+from pathlib import Path
+from typing import Any, Dict, List, Optional, Tuple
+
+from ..schema import EndpointDefinition, EnumDefinition, FieldDefinition, ModelDefinition
+from .base import BaseExtractor
+
+_YAML_HINT = (
+    "Reading a YAML spec requires PyYAML. Install it with:\n"
+    "    pip install pyyaml\n"
+    "(JSON specs need nothing beyond the standard library.)"
+)
+
+# OpenAPI `format` is more specific than `type`, so it wins where both are set.
+_FORMAT_HINTS: Dict[str, Any] = {
+    "date-time": "datetime",
+    "date": "datetime",
+    "uuid": "UUID",
+    "binary": "bytes",
+    "byte": "bytes",
+    "int64": "bigint",
+}
+
+_TYPE_HINTS: Dict[str, Any] = {
+    "string": str,
+    "integer": int,
+    "number": float,
+    "boolean": bool,
+    "array": "list",
+    "object": "dict",
+}
+
+# Response codes worth reading a body off, best first. "default" is last
+# because a spec that defines it usually means the error case.
+_STATUS_PREFERENCE = ("200", "201", "2XX", "202", "203", "204", "default")
+
+
+def _to_model_name(name: str) -> str:
+    """Convert a schema name to PascalCase (pet_category -> PetCategory)."""
+    parts = [p for p in re.split(r"[^0-9a-zA-Z]+", name) if p]
+    return "".join(p[:1].upper() + p[1:] for p in parts) or name
+
+
+def _to_member_name(value: Any) -> str:
+    """Convert an enum value to a legal Python identifier."""
+    name = re.sub(r"[^0-9a-zA-Z]+", "_", str(value)).strip("_").upper()
+    if not name:
+        return "EMPTY"
+    if name[0].isdigit():
+        return f"V_{name}"
+    return name
+
+
+def _load_document(path: Path) -> dict:
+    """Parse a spec file. JSON via stdlib; YAML only if PyYAML is installed."""
+    text = path.read_text()
+
+    if path.suffix.lower() in (".yaml", ".yml"):
+        try:
+            import yaml
+        except ImportError as e:  # pragma: no cover - exercised only without the extra
+            raise RuntimeError(_YAML_HINT) from e
+        return yaml.safe_load(text) or {}
+
+    try:
+        return json.loads(text)
+    except ValueError:
+        # A spec is often handed over with no extension or a wrong one, so fall
+        # back to YAML rather than failing on what is really a naming mistake.
+        try:
+            import yaml
+        except ImportError as e:
+            raise ValueError(
+                f"{path} is not valid JSON, and YAML support is unavailable.\n{_YAML_HINT}"
+            ) from e
+        return yaml.safe_load(text) or {}
+
+
+class OpenAPIExtractor(BaseExtractor):
+    """Extracts modelgen IR from an OpenAPI 3.x / Swagger 2.0 document."""
+
+    def __init__(self, source_path):
+        super().__init__(source_path)
+        self._doc: Optional[dict] = None
+        self._enums: Dict[str, EnumDefinition] = {}
+        self._enum_types: Dict[str, type] = {}
+
+    # ── document access ────────────────────────────────────────────────────
+
+    @property
+    def doc(self) -> dict:
+        if self._doc is None:
+            self._doc = _load_document(self.source_path)
+        return self._doc
+
+    @property
+    def is_swagger2(self) -> bool:
+        return "swagger" in self.doc and "openapi" not in self.doc
+
+    def _schemas(self) -> Dict[str, dict]:
+        """Named schemas, wherever this spec version keeps them."""
+        if self.is_swagger2:
+            return self.doc.get("definitions", {}) or {}
+        return (self.doc.get("components", {}) or {}).get("schemas", {}) or {}
+
+    def detect(self) -> bool:
+        """True when the source is a parseable document declaring a spec version."""
+        if not self.source_path.is_file():
+            return False
+        if self.source_path.suffix.lower() not in (".json", ".yaml", ".yml"):
+            return False
+        try:
+            doc = self.doc
+        except Exception:
+            return False
+        return isinstance(doc, dict) and ("openapi" in doc or "swagger" in doc)
+
+    # ── $ref plumbing ──────────────────────────────────────────────────────
+
+    @staticmethod
+    def _ref_name(ref: str) -> str:
+        return _to_model_name(ref.rsplit("/", 1)[-1])
+
+    def _deref(self, schema: Any, _seen: Optional[set] = None) -> dict:
+        """Follow $ref chains to the schema they land on."""
+        if not isinstance(schema, dict):
+            return {}
+        seen = _seen or set()
+        ref = schema.get("$ref")
+        if not ref or ref in seen:
+            return schema
+        seen.add(ref)
+        target = self.doc
+        for part in ref.lstrip("#/").split("/"):
+            if not isinstance(target, dict):
+                return {}
+            target = target.get(part, {})
+        return self._deref(target, seen)
+
+    def _flatten(self, schema: dict) -> Tuple[Dict[str, dict], List[str]]:
+        """Resolve allOf/$ref into one property map plus the required names."""
+        schema = self._deref(schema)
+        props: Dict[str, dict] = {}
+        required: List[str] = []
+
+        for sub in schema.get("allOf", []) or []:
+            sub_props, sub_required = self._flatten(sub)
+            props.update(sub_props)
+            required.extend(sub_required)
+
+        # anyOf/oneOf describe alternatives, not a single shape. Taking the
+        # first branch's properties beats emitting an empty model — a shunt
+        # answering with one valid variant is more useful than one answering {}.
+        for key in ("oneOf", "anyOf"):
+            for sub in (schema.get(key) or [])[:1]:
+                sub_props, sub_required = self._flatten(sub)
+                props.update(sub_props)
+                required.extend(sub_required)
+
+        props.update(schema.get("properties", {}) or {})
+        required.extend(schema.get("required", []) or [])
+        return props, required
+
+    # ── type resolution ────────────────────────────────────────────────────
+
+    def _register_enum(self, owner: str, field_name: str, values: List[Any]) -> type:
+        """Materialise a spec enum as a real Enum class, deduped by value set."""
+        name = f"{_to_model_name(owner)}{_to_model_name(field_name)}"
+        pairs = [(_to_member_name(v), str(v)) for v in values]
+
+        # Two fields can legitimately declare the same enum name with different
+        # members; suffix rather than let the second silently win.
+        existing = self._enums.get(name)
+        if existing and existing.values != pairs:
+            suffix = 2
+            while f"{name}{suffix}" in self._enums and (
+                self._enums[f"{name}{suffix}"].values != pairs
+            ):
+                suffix += 1
+            name = f"{name}{suffix}"
+
+        if name not in self._enums:
+            self._enums[name] = EnumDefinition(name=name, values=pairs)
+            self._enum_types[name] = Enum(name, pairs)
+        return self._enum_types[name]
+
+    def _resolve(
+        self, owner: str, field_name: str, prop: dict
+    ) -> Tuple[Any, Optional[str], bool]:
+        """Map a property schema to (type_hint, foreign_key, many)."""
+        ref = prop.get("$ref")
+        if ref:
+            target = self._ref_name(ref)
+            resolved = self._deref(prop)
+            # A $ref to an enum or a plain scalar is not a relationship — only
+            # a ref to an object shape is.
+            if resolved.get("enum"):
+                return self._register_enum(owner, field_name, resolved["enum"]), None, False
+            if resolved.get("type") in _TYPE_HINTS and resolved.get("type") != "object":
+                return self._resolve(owner, field_name, resolved)
+            return "dict", target, False
+
+        if prop.get("enum") and prop.get("type", "string") == "string":
+            return self._register_enum(owner, field_name, prop["enum"]), None, False
+
+        if prop.get("allOf") or prop.get("oneOf") or prop.get("anyOf"):
+            branch = (
+                (prop.get("allOf") or prop.get("oneOf") or prop.get("anyOf")) or [{}]
+            )[0]
+            if branch.get("$ref"):
+                return "dict", self._ref_name(branch["$ref"]), False
+            return self._resolve(owner, field_name, self._deref(branch))
+
+        prop_type = prop.get("type")
+
+        if prop_type == "array":
+            items = prop.get("items", {}) or {}
+            if items.get("$ref"):
+                inner = self._deref(items)
+                if inner.get("type", "object") == "object":
+                    return "list", self._ref_name(items["$ref"]), True
+            return "list", None, False
+
+        fmt = prop.get("format")
+        if fmt in _FORMAT_HINTS:
+            return _FORMAT_HINTS[fmt], None, False
+
+        return _TYPE_HINTS.get(prop_type, str), None, False
+
+    # ── extraction ─────────────────────────────────────────────────────────
+
+    def extract(self) -> Tuple[List[ModelDefinition], List[EnumDefinition]]:
+        self._enums = {}
+        self._enum_types = {}
+
+        models: List[ModelDefinition] = []
+        for raw_name, schema in self._schemas().items():
+            model_name = _to_model_name(raw_name)
+            schema = schema or {}
+
+            # A top-level enum is a type, not a shape — register it and skip.
+            if schema.get("enum") and not schema.get("properties"):
+                self._register_enum(model_name, "", schema["enum"])
+                continue
+
+            props, required = self._flatten(schema)
+            required_set = set(required)
+
+            fields: List[FieldDefinition] = []
+            for prop_name, prop in props.items():
+                prop = prop or {}
+                type_hint, fk, many = self._resolve(model_name, prop_name, prop)
+                is_pk = prop_name == "id" or prop_name == f"{raw_name.lower()}_id"
+                fields.append(
+                    FieldDefinition(
+                        name=prop_name,
+                        type_hint=type_hint,
+                        default=prop.get("default"),
+                        optional=prop_name not in required_set and not is_pk,
+                        primary_key=is_pk,
+                        foreign_key=fk,
+                        many=many,
+                    )
+                )
+
+            models.append(
+                ModelDefinition(
+                    name=model_name,
+                    fields=fields,
+                    docstring=schema.get("description") or schema.get("title"),
+                )
+            )
+
+        return models, list(self._enums.values())
+
+    # ── endpoints ──────────────────────────────────────────────────────────
+
+    def endpoints(self) -> List[EndpointDefinition]:
+        """Every operation in the document, normalised for routing."""
+        out: List[EndpointDefinition] = []
+        base = self.doc.get("basePath", "") if self.is_swagger2 else ""
+
+        for path, item in (self.doc.get("paths", {}) or {}).items():
+            if not isinstance(item, dict):
+                continue
+            shared_params = item.get("parameters", []) or []
+
+            for method, op in item.items():
+                if method.lower() not in (
+                    "get", "post", "put", "patch", "delete", "head", "options"
+                ):
+                    continue
+                if not isinstance(op, dict):
+                    continue
+
+                status, response_schema, example = self._response(op)
+                request_model = self._request_model(op, shared_params)
+                response_model, is_list, envelope = self._schema_target(response_schema)
+
+                full_path = f"{base.rstrip('/')}{path}" if base else path
+                model = response_model or request_model
+
+                if is_list:
+                    kind = "collection"
+                elif re.search(r"\{[^}]+\}$", full_path):
+                    kind = "item"
+                elif method.lower() == "post" and model:
+                    kind = "collection"
+                else:
+                    kind = "action"
+
+                out.append(
+                    EndpointDefinition(
+                        method=method.upper(),
+                        path=full_path,
+                        operation_id=op.get("operationId"),
+                        summary=op.get("summary") or op.get("description"),
+                        kind=kind,
+                        model=model,
+                        request_model=request_model,
+                        response_model=response_model,
+                        response_is_list=is_list,
+                        envelope_key=envelope,
+                        status=status,
+                        path_params=re.findall(r"\{([^}]+)\}", full_path),
+                        example=example,
+                    )
+                )
+
+        return out
+
+    def _response(self, op: dict) -> Tuple[int, dict, Any]:
+        """Pick the success response and return (status, schema, example)."""
+        responses = op.get("responses", {}) or {}
+        codes = [str(c) for c in responses]
+
+        chosen = next((c for c in _STATUS_PREFERENCE if c in codes), None)
+        if chosen is None:
+            chosen = next((c for c in sorted(codes) if c.startswith("2")), None)
+        if chosen is None:
+            return 200, {}, None
+
+        body = responses.get(chosen) or responses.get(int(chosen), {}) or {}
+        status = 200 if chosen in ("default", "2XX") else int(chosen)
+
+        if self.is_swagger2:
+            return status, body.get("schema", {}) or {}, body.get("examples")
+
+        content = body.get("content", {}) or {}
+        media = content.get("application/json") or next(
+            (v for k, v in content.items() if "json" in k), {}
+        )
+        example = media.get("example")
+        if example is None:
+            examples = media.get("examples") or {}
+            first = next(iter(examples.values()), None)
+            if isinstance(first, dict):
+                example = first.get("value")
+        return status, media.get("schema", {}) or {}, example
+
+    def _request_model(self, op: dict, shared_params: list) -> Optional[str]:
+        if self.is_swagger2:
+            params = list(shared_params) + list(op.get("parameters", []) or [])
+            for param in params:
+                if isinstance(param, dict) and param.get("in") == "body":
+                    name, _, _ = self._schema_target(param.get("schema", {}) or {})
+                    return name
+            return None
+
+        body = op.get("requestBody") or {}
+        content = self._deref(body).get("content", {}) or {}
+        media = content.get("application/json") or next(
+            (v for k, v in content.items() if "json" in k), {}
+        )
+        name, _, _ = self._schema_target(media.get("schema", {}) or {})
+        return name
+
+    def _schema_target(
+        self, schema: dict
+    ) -> Tuple[Optional[str], bool, Optional[str]]:
+        """Return (model name, is_list, envelope key) for a request/response schema."""
+        if not isinstance(schema, dict) or not schema:
+            return None, False, None
+
+        if schema.get("$ref"):
+            resolved = self._deref(schema)
+            # A named wrapper (PetPage) is still a wrapper; look through it.
+            if resolved.get("type") == "array" or resolved.get("properties"):
+                inner = self._schema_target(resolved)
+                if inner[0]:
+                    return inner
+            return self._ref_name(schema["$ref"]), False, None
+
+        if schema.get("type") == "array":
+            items = schema.get("items", {}) or {}
+            if items.get("$ref"):
+                return self._ref_name(items["$ref"]), True, None
+            return None, True, None
+
+        # A wrapped collection — {"items": [...], "total": n} and friends.
+        for prop_name, prop in (schema.get("properties", {}) or {}).items():
+            if prop_name in ("items", "results", "data") and (prop or {}).get(
+                "type"
+            ) == "array":
+                inner = (prop.get("items") or {}).get("$ref")
+                if inner:
+                    return self._ref_name(inner), True, prop_name
+
+        for key in ("allOf", "oneOf", "anyOf"):
+            for sub in (schema.get(key) or [])[:1]:
+                return self._schema_target(sub)
+
+        return None, False, None
diff --git a/soleprint/station/tools/modelgen/loader/extract/tabular.py b/soleprint/station/tools/modelgen/loader/extract/tabular.py
new file mode 100644
index 0000000..a33e425
--- /dev/null
+++ b/soleprint/station/tools/modelgen/loader/extract/tabular.py
@@ -0,0 +1,450 @@
+"""
+Tabular Extractor
+
+Turns a directory of spreadsheets into modelgen's IR — one model per CSV file,
+one per sheet inside an ODS workbook — and keeps the rows.
+
+    extractor = TabularExtractor("./sheets")
+    models, enums = extractor.extract()   # the shapes  (BaseExtractor contract)
+    datasets      = extractor.datasets()  # the rows    (what shuntgen seeds with)
+
+ODS is read with zipfile + ElementTree rather than odfpy or pandas. An .ods is
+a zip with an XML part in it, and reading it directly is what lets modelgen keep
+its "no dependencies" promise — the same promise that makes it publishable as a
+standalone pip package.
+
+Types are inferred per column from the values actually present, and blanks make
+a column optional. Keys are inferred by name and confirmed by the data: an `id`
+column that is neither unique nor complete is not treated as a primary key, and
+a `customer_id` column is only a foreign key if a matching table exists.
+"""
+
+import csv
+import re
+import zipfile
+from datetime import date, datetime
+from pathlib import Path
+from typing import Any, Dict, List, Optional, Tuple
+from uuid import UUID
+from xml.etree import ElementTree
+
+from ..schema import (
+    DatasetDefinition,
+    EnumDefinition,
+    FieldDefinition,
+    ModelDefinition,
+)
+from .base import BaseExtractor
+
+SUFFIXES = (".csv", ".tsv", ".ods")
+
+_TABLE = "{urn:oasis:names:tc:opendocument:xmlns:table:1.0}"
+_OFFICE = "{urn:oasis:names:tc:opendocument:xmlns:office:1.0}"
+
+# ODS pads every sheet out to the full grid with repeat counts in the thousands.
+# Expanding those verbatim would turn a 5-column sheet into a 1024-column one,
+# so repeats are honoured only up to a width a real sheet could plausibly have.
+_MAX_COLS = 512
+_MAX_ROWS = 100_000
+
+_TRUE = {"true", "yes", "y", "t"}
+_FALSE = {"false", "no", "n", "f"}
+
+# Ordered widest-last: the first format that parses every value in the column
+# wins, so a stricter pattern must be offered before a looser one.
+_DATE_FORMATS = ("%Y-%m-%d", "%d/%m/%Y", "%m/%d/%Y", "%Y/%m/%d")
+_DATETIME_FORMATS = (
+    "%Y-%m-%dT%H:%M:%S",
+    "%Y-%m-%dT%H:%M",
+    "%Y-%m-%d %H:%M:%S",
+    "%Y-%m-%d %H:%M",
+)
+
+
+def _to_model_name(name: str) -> str:
+    """Convert a file or sheet name to PascalCase (line_items -> LineItems)."""
+    parts = [p for p in re.split(r"[^0-9a-zA-Z]+", name) if p]
+    return "".join(p[:1].upper() + p[1:] for p in parts) or name
+
+
+def _to_slug(name: str) -> str:
+    """Convert a file or sheet name to a url-safe collection name."""
+    slug = re.sub(r"[^0-9a-zA-Z]+", "-", name).strip("-").lower()
+    return slug or "items"
+
+
+def _singular(word: str) -> str:
+    """Crude singulariser — enough to match a `customer_id` to a `customers` sheet."""
+    word = word.lower()
+    if word.endswith("ies") and len(word) > 3:
+        return word[:-3] + "y"
+    for ending in ("ches", "shes", "sses", "xes", "zes"):
+        if word.endswith(ending):
+            return word[: -len(ending) + 1]
+    if word.endswith("s") and not word.endswith("ss"):
+        return word[:-1]
+    return word
+
+
+# ── readers ────────────────────────────────────────────────────────────────
+
+
+def _read_delimited(path: Path) -> List[List[str]]:
+    """Read a CSV/TSV into a grid of raw strings."""
+    delimiter = "\t" if path.suffix.lower() == ".tsv" else ","
+    with path.open(newline="", encoding="utf-8-sig") as fh:
+        return [row for row in csv.reader(fh, delimiter=delimiter)]
+
+
+def _cell_text(cell: ElementTree.Element) -> str:
+    """The displayed text of an ODS cell, typed value preferred over its label."""
+    value_type = cell.get(f"{_OFFICE}value-type")
+    for attr in ("value", "date-value", "time-value", "boolean-value"):
+        raw = cell.get(f"{_OFFICE}{attr}")
+        if raw is not None:
+            return raw
+    if value_type == "string" or value_type is None:
+        return "".join(cell.itertext()).strip()
+    return "".join(cell.itertext()).strip()
+
+
+def _read_ods(path: Path) -> Dict[str, List[List[str]]]:
+    """Read an ODS workbook into {sheet name: grid of raw strings}."""
+    with zipfile.ZipFile(path) as archive:
+        try:
+            content = archive.read("content.xml")
+        except KeyError as e:
+            raise ValueError(f"{path} is not a readable ODS file (no content.xml)") from e
+
+    root = ElementTree.fromstring(content)
+    sheets: Dict[str, List[List[str]]] = {}
+
+    for table in root.iter(f"{_TABLE}table"):
+        name = table.get(f"{_TABLE}name") or f"sheet{len(sheets) + 1}"
+        grid: List[List[str]] = []
+
+        for row in table.iter(f"{_TABLE}table-row"):
+            cells: List[str] = []
+            for cell in row:
+                if cell.tag not in (
+                    f"{_TABLE}table-cell",
+                    f"{_TABLE}covered-table-cell",
+                ):
+                    continue
+                repeat = int(cell.get(f"{_TABLE}number-columns-repeated", 1) or 1)
+                text = "" if cell.tag.endswith("covered-table-cell") else _cell_text(cell)
+                # Padding is always empty and always repeated; a real repeated
+                # value is worth expanding, an empty run at the end is not.
+                if not text and repeat > 1 and len(cells) + repeat > _MAX_COLS:
+                    break
+                cells.extend([text] * min(repeat, _MAX_COLS - len(cells)))
+                if len(cells) >= _MAX_COLS:
+                    break
+
+            while cells and not cells[-1].strip():
+                cells.pop()
+
+            row_repeat = int(row.get(f"{_TABLE}number-rows-repeated", 1) or 1)
+            if not cells:
+                # A repeated blank row is padding; a single one may be a gap.
+                if row_repeat == 1 and grid:
+                    grid.append([])
+                continue
+            for _ in range(min(row_repeat, _MAX_ROWS - len(grid))):
+                grid.append(list(cells))
+
+        if grid:
+            sheets[name] = grid
+
+    return sheets
+
+
+# ── inference ──────────────────────────────────────────────────────────────
+
+
+def _parse_bool(value: str) -> Optional[bool]:
+    lowered = value.strip().lower()
+    if lowered in _TRUE:
+        return True
+    if lowered in _FALSE:
+        return False
+    return None
+
+
+def _parse_int(value: str) -> Optional[int]:
+    text = value.strip()
+    # A float-shaped string must not read as an int, or a column of prices
+    # silently truncates.
+    if not re.fullmatch(r"[+-]?\d+", text):
+        return None
+    try:
+        return int(text)
+    except ValueError:
+        return None
+
+
+def _parse_float(value: str) -> Optional[float]:
+    try:
+        return float(value.strip())
+    except ValueError:
+        return None
+
+
+def _parse_uuid(value: str) -> Optional[str]:
+    try:
+        return str(UUID(value.strip()))
+    except (ValueError, AttributeError):
+        return None
+
+
+def _parse_temporal(value: str) -> Optional[str]:
+    """Parse a date/datetime into an ISO string, or None."""
+    text = value.strip()
+    if not text:
+        return None
+    for fmt in _DATETIME_FORMATS:
+        try:
+            return datetime.strptime(text, fmt).isoformat()
+        except ValueError:
+            continue
+    for fmt in _DATE_FORMATS:
+        try:
+            return datetime.strptime(text, fmt).date().isoformat()
+        except ValueError:
+            continue
+    # ODS writes ISO-8601 with a timezone or fractional seconds; let the
+    # stdlib parser have the ones the explicit formats miss.
+    try:
+        return datetime.fromisoformat(text.replace("Z", "+00:00")).isoformat()
+    except ValueError:
+        return None
+
+
+# Each entry is (type hint, parser). Order is the precedence: the first type
+# every value in the column satisfies wins, so narrow types come first.
+_CANDIDATES: List[Tuple[Any, Any]] = [
+    (bool, _parse_bool),
+    (int, _parse_int),
+    (float, _parse_float),
+    ("UUID", _parse_uuid),
+    ("datetime", _parse_temporal),
+]
+
+
+def _infer_column(values: List[str]) -> Tuple[Any, Any]:
+    """Return (type_hint, coercer) for a column, from its non-blank values."""
+    present = [v for v in values if v is not None and str(v).strip() != ""]
+    if not present:
+        return str, lambda v: v
+
+    for type_hint, parser in _CANDIDATES:
+        if all(parser(v) is not None for v in present):
+            return type_hint, parser
+
+    return str, lambda v: v.strip() if isinstance(v, str) else v
+
+
+# ── extractor ──────────────────────────────────────────────────────────────
+
+
+class TabularExtractor(BaseExtractor):
+    """Extracts modelgen IR and seed rows from a directory of spreadsheets."""
+
+    def __init__(self, source_path):
+        super().__init__(source_path)
+        self._datasets: List[DatasetDefinition] = []
+
+    def detect(self) -> bool:
+        """True when the source is a directory holding at least one sheet."""
+        if self.source_path.is_file():
+            return self.source_path.suffix.lower() in SUFFIXES
+        if not self.source_path.is_dir():
+            return False
+        return any(self._sources())
+
+    def _sources(self) -> List[Path]:
+        if self.source_path.is_file():
+            return [self.source_path]
+        return sorted(
+            p
+            for p in self.source_path.iterdir()
+            if p.is_file() and p.suffix.lower() in SUFFIXES and not p.name.startswith(".")
+        )
+
+    def datasets(self) -> List[DatasetDefinition]:
+        """Seed rows harvested by the last extract() call."""
+        if not self._datasets:
+            self.extract()
+        return self._datasets
+
+    def extract(self) -> Tuple[List[ModelDefinition], List[EnumDefinition]]:
+        grids: List[Tuple[str, str, List[List[str]]]] = []  # (label, source, grid)
+
+        for path in self._sources():
+            if path.suffix.lower() == ".ods":
+                for sheet_name, grid in _read_ods(path).items():
+                    grids.append((sheet_name, f"{path.name}#{sheet_name}", grid))
+            else:
+                grids.append((path.stem, path.name, _read_delimited(path)))
+
+        if not grids:
+            raise ValueError(f"No .csv/.tsv/.ods files found in {self.source_path}")
+
+        # Names have to be known before fields, because a foreign key is only a
+        # foreign key when the table it points at is one of the others.
+        known: Dict[str, str] = {}
+        for label, _, _ in grids:
+            model_name = _to_model_name(label)
+            known[_singular(label)] = model_name
+            known[label.lower()] = model_name
+
+        models: List[ModelDefinition] = []
+        self._datasets = []
+
+        for label, source, grid in grids:
+            parsed = self._build(label, source, grid, known)
+            if parsed:
+                model, dataset = parsed
+                models.append(model)
+                self._datasets.append(dataset)
+
+        return models, []
+
+    def _build(
+        self,
+        label: str,
+        source: str,
+        grid: List[List[str]],
+        known: Dict[str, str],
+    ) -> Optional[Tuple[ModelDefinition, DatasetDefinition]]:
+        rows = [r for r in grid if any(str(c).strip() for c in r)]
+        if not rows:
+            return None
+
+        headers = self._headers(rows[0])
+        if not headers:
+            return None
+
+        body = rows[1:]
+        columns: Dict[str, List[str]] = {h: [] for h in headers}
+        for row in body:
+            for index, header in enumerate(headers):
+                columns[header].append(row[index] if index < len(row) else "")
+
+        model_name = _to_model_name(label)
+        pk = self._primary_key(label, model_name, headers, columns, len(body), known)
+
+        fields: List[FieldDefinition] = []
+        coercers: Dict[str, Any] = {}
+
+        for header in headers:
+            values = columns[header]
+            type_hint, coercer = _infer_column(values)
+            coercers[header] = coercer
+
+            is_pk = header == pk
+            fk = None if is_pk else self._foreign_key(header, model_name, known)
+            has_blank = any(str(v).strip() == "" for v in values)
+
+            fields.append(
+                FieldDefinition(
+                    name=header,
+                    type_hint=type_hint,
+                    default=None,
+                    optional=has_blank and not is_pk,
+                    primary_key=is_pk,
+                    foreign_key=fk,
+                    unique=is_pk,
+                )
+            )
+
+        typed_rows: List[Dict[str, Any]] = []
+        for row in body:
+            record: Dict[str, Any] = {}
+            for index, header in enumerate(headers):
+                raw = row[index] if index < len(row) else ""
+                if str(raw).strip() == "":
+                    record[header] = None
+                    continue
+                parsed = coercers[header](raw)
+                record[header] = raw.strip() if parsed is None else parsed
+            typed_rows.append(record)
+
+        model = ModelDefinition(
+            name=model_name,
+            fields=fields,
+            docstring=f"Imported from {source} ({len(typed_rows)} rows).",
+        )
+        dataset = DatasetDefinition(
+            model=model_name,
+            rows=typed_rows,
+            source=source,
+            collection=_to_slug(label),
+        )
+        return model, dataset
+
+    @staticmethod
+    def _headers(row: List[str]) -> List[str]:
+        """Normalise the header row, filling blanks and de-duplicating."""
+        headers: List[str] = []
+        seen: Dict[str, int] = {}
+        for index, raw in enumerate(row):
+            name = re.sub(r"[^0-9a-zA-Z]+", "_", str(raw).strip()).strip("_").lower()
+            if not name:
+                name = f"column_{index + 1}"
+            if name[0].isdigit():
+                name = f"c_{name}"
+            if name in seen:
+                seen[name] += 1
+                name = f"{name}_{seen[name]}"
+            else:
+                seen[name] = 1
+            headers.append(name)
+        return headers
+
+    @classmethod
+    def _primary_key(
+        cls,
+        label: str,
+        model_name: str,
+        headers: List[str],
+        columns: Dict[str, List[str]],
+        row_count: int,
+        known: Dict[str, str],
+    ) -> Optional[str]:
+        """Pick the key column — named like one, and unique and complete in fact."""
+
+        def holds(header: str) -> bool:
+            values = [str(v).strip() for v in columns[header]]
+            return bool(row_count) and all(values) and len(set(values)) == row_count
+
+        stem = _singular(label)
+        for candidate in ("id", f"{stem}_id", f"{label.lower()}_id"):
+            if candidate in headers and holds(candidate):
+                return candidate
+
+        # A sheet may name its key after the row rather than the table —
+        # `line_id` in a `line_items` sheet. Accept the leading column when it
+        # is shaped like a key, holds like one, and does not point elsewhere.
+        if headers:
+            first = headers[0]
+            if (
+                (first == "id" or first.endswith("_id"))
+                and cls._foreign_key(first, model_name, known) is None
+                and holds(first)
+            ):
+                return first
+        return None
+
+    @staticmethod
+    def _foreign_key(
+        header: str, model_name: str, known: Dict[str, str]
+    ) -> Optional[str]:
+        """A `<thing>_id` column pointing at another sheet in the same import."""
+        if not header.endswith("_id"):
+            return None
+        stem = header[:-3]
+        target = known.get(_singular(stem)) or known.get(stem)
+        if target and target != model_name:
+            return target
+        return None
diff --git a/soleprint/station/tools/modelgen/loader/schema.py b/soleprint/station/tools/modelgen/loader/schema.py
index ac8705e..a2c01ce 100644
--- a/soleprint/station/tools/modelgen/loader/schema.py
+++ b/soleprint/station/tools/modelgen/loader/schema.py
@@ -13,7 +13,7 @@ Expects the folder to have an __init__.py that exports:
 import dataclasses as dc
 import importlib.util
 import sys
-from dataclasses import dataclass
+from dataclasses import dataclass, field
 from enum import Enum
 from pathlib import Path
 from typing import Any, Dict, List, Optional, Type, get_type_hints
@@ -32,6 +32,10 @@ class FieldDefinition:
     primary_key: bool = False
     foreign_key: Optional[str] = None  # target model name
     unique: bool = False
+    # True when foreign_key points at many rows rather than one — an array of
+    # $ref, a m2m table. graphgen renders the two differently, so losing the
+    # distinction would draw every collection as a single edge.
+    many: bool = False
 
 
 @dataclass
@@ -60,6 +64,51 @@ class GrpcServiceDefinition:
     methods: List[Dict[str, Any]]
 
 
+@dataclass
+class EndpointDefinition:
+    """Represents one HTTP operation on a service.
+
+    Models describe the shapes a service passes around; endpoints describe how
+    it is called. Loaders that read a service contract (OpenAPI) or infer one
+    (tabular) emit these alongside the models, and shuntgen turns them into
+    routes. Loaders that only see shapes — dataclasses, a Django app — emit
+    none, which is why this is not part of the BaseExtractor contract.
+    """
+
+    method: str  # GET, POST, ...
+    path: str  # /pets/{petId}
+    operation_id: Optional[str] = None
+    summary: Optional[str] = None
+    # "collection" returns/accepts many, "item" one, "action" neither.
+    kind: str = "item"
+    model: Optional[str] = None  # what this operation is about
+    request_model: Optional[str] = None
+    response_model: Optional[str] = None
+    response_is_list: bool = False
+    # Set when the collection arrives wrapped — {"items": [...], "total": n}
+    # rather than a bare array. Answering a wrapped endpoint with an array is
+    # the kind of mismatch a client only discovers at parse time.
+    envelope_key: Optional[str] = None
+    status: int = 200
+    path_params: List[str] = field(default_factory=list)
+    example: Any = None  # response example carried through from the source
+
+
+@dataclass
+class DatasetDefinition:
+    """Concrete rows harvested next to a model.
+
+    Importing a spreadsheet yields both a shape and the data that shaped it.
+    Throwing the rows away would mean generating a service that answers with
+    invented values when the real ones were right there.
+    """
+
+    model: str
+    rows: List[Dict[str, Any]] = field(default_factory=list)
+    source: Optional[str] = None  # file the rows came from
+    collection: Optional[str] = None  # url-facing name, e.g. "customers"
+
+
 class SchemaLoader:
     """Loads model definitions from Python dataclasses in schema/ folder."""
 
diff --git a/soleprint/station/tools/modelgen/tests/__init__.py b/soleprint/station/tools/modelgen/tests/__init__.py
new file mode 100644
index 0000000..0ad1bba
--- /dev/null
+++ b/soleprint/station/tools/modelgen/tests/__init__.py
@@ -0,0 +1,18 @@
+"""
+Tests for modelgen.
+
+Run from station/tools/, not from inside modelgen/ — the package ships a
+types.py, and having its own directory on sys.path shadows the standard
+library module of that name:
+
+    cd soleprint/station/tools
+    python -m unittest modelgen.tests.test_extractors
+
+stdlib unittest only, and every input is built in a temp directory. modelgen is
+published as a standalone pip package, so its tests have to pass with nothing
+installed and nothing else in the tree.
+
+These are unit tests of the loaders and generators. They are not contract
+tests — those talk HTTP, belong to a room, and are never committed to core
+(see station/tools/tester/tests/README.md).
+"""
diff --git a/soleprint/station/tools/modelgen/tests/test_extractors.py b/soleprint/station/tools/modelgen/tests/test_extractors.py
new file mode 100644
index 0000000..3116fab
--- /dev/null
+++ b/soleprint/station/tools/modelgen/tests/test_extractors.py
@@ -0,0 +1,406 @@
+"""
+Tests for the OpenAPI and tabular extractors and the datagen target.
+
+stdlib unittest and nothing else, and every input is built in a temp directory
+rather than read from a fixture file — modelgen is published as a standalone
+package, so its tests have to pass with nothing installed and nothing else in
+the tree.
+
+    cd soleprint/station/tools && python -m unittest modelgen.tests.test_extractors
+
+Run it from station/tools/, not from inside modelgen/: modelgen ships a
+types.py, and putting the package's own directory on sys.path shadows the
+standard library module of that name.
+"""
+
+import json
+import shutil
+import sys
+import tempfile
+import unittest
+import zipfile
+from enum import Enum
+from pathlib import Path
+
+sys.path.insert(0, str(Path(__file__).resolve().parents[1].parent))
+
+from modelgen.generator import GENERATORS, DatagenGenerator  # noqa: E402
+from modelgen.loader.extract.openapi import OpenAPIExtractor  # noqa: E402
+from modelgen.loader.extract.tabular import TabularExtractor  # noqa: E402
+
+SPEC = {
+    "openapi": "3.0.3",
+    "info": {"title": "Zoo", "version": "1.0.0"},
+    "paths": {
+        "/pets": {
+            "get": {
+                "operationId": "listPets",
+                "responses": {
+                    "200": {
+                        "content": {
+                            "application/json": {
+                                "schema": {"$ref": "#/components/schemas/PetPage"}
+                            }
+                        }
+                    }
+                },
+            },
+            "post": {
+                "operationId": "createPet",
+                "requestBody": {
+                    "content": {
+                        "application/json": {
+                            "schema": {"$ref": "#/components/schemas/Pet"}
+                        }
+                    }
+                },
+                "responses": {
+                    "201": {
+                        "content": {
+                            "application/json": {
+                                "schema": {"$ref": "#/components/schemas/Pet"}
+                            }
+                        }
+                    }
+                },
+            },
+        },
+        "/pets/{petId}": {
+            "get": {
+                "operationId": "getPet",
+                "responses": {
+                    "200": {
+                        "content": {
+                            "application/json": {
+                                "schema": {"$ref": "#/components/schemas/Pet"},
+                                "example": {"id": 7, "name": "Rocinante"},
+                            }
+                        }
+                    }
+                },
+            }
+        },
+    },
+    "components": {
+        "schemas": {
+            "Pet": {
+                "type": "object",
+                "description": "An animal.",
+                "required": ["id", "name"],
+                "properties": {
+                    "id": {"type": "integer", "format": "int64"},
+                    "name": {"type": "string"},
+                    "status": {"type": "string", "enum": ["available", "sold"]},
+                    "weight": {"type": "number"},
+                    "born_on": {"type": "string", "format": "date"},
+                    "category": {"$ref": "#/components/schemas/Category"},
+                    "tags": {
+                        "type": "array",
+                        "items": {"$ref": "#/components/schemas/Category"},
+                    },
+                },
+            },
+            "Category": {
+                "type": "object",
+                "required": ["id"],
+                "properties": {
+                    "id": {"type": "integer"},
+                    "name": {"type": "string"},
+                },
+            },
+            "PetPage": {
+                "type": "object",
+                "properties": {
+                    "items": {
+                        "type": "array",
+                        "items": {"$ref": "#/components/schemas/Pet"},
+                    },
+                    "total": {"type": "integer"},
+                },
+            },
+        }
+    },
+}
+
+CUSTOMERS_CSV = """id,name,email,active,joined,balance
+1,Ada,ada@example.com,true,2024-03-11,150.5
+2,Bruno,bruno@example.com,false,2024-05-02,80
+3,Camila,camila@example.com,true,2023-11-27,
+"""
+
+ORDERS_CSV = """order_id,customer_id,total,placed
+1001,1,42.00,2025-02-03
+1002,2,15.25,2025-03-14
+"""
+
+
+def write_ods(path: Path, sheet: str, rows: list[list[str]]) -> None:
+    """A minimal ODS, padded the way a real one is."""
+    ns = (
+        'xmlns:office="urn:oasis:names:tc:opendocument:xmlns:office:1.0" '
+        'xmlns:table="urn:oasis:names:tc:opendocument:xmlns:table:1.0" '
+        'xmlns:text="urn:oasis:names:tc:opendocument:xmlns:text:1.0"'
+    )
+
+    def cell(value: str) -> str:
+        if value == "":
+            return "<table:table-cell/>"
+        return (
+            '<table:table-cell office:value-type="string">'
+            f"<text:p>{value}</text:p></table:table-cell>"
+        )
+
+    body = "".join(
+        "<table:table-row>"
+        + "".join(cell(c) for c in row)
+        + '<table:table-cell table:number-columns-repeated="1018"/>'
+        "</table:table-row>"
+        for row in rows
+    )
+    content = (
+        '<?xml version="1.0" encoding="UTF-8"?>'
+        f"<office:document-content {ns}>"
+        "<office:body><office:spreadsheet>"
+        f'<table:table table:name="{sheet}">{body}'
+        '<table:table-row table:number-rows-repeated="1048570">'
+        '<table:table-cell table:number-columns-repeated="1024"/></table:table-row>'
+        "</table:table></office:spreadsheet></office:body></office:document-content>"
+    )
+    with zipfile.ZipFile(path, "w") as archive:
+        archive.writestr("content.xml", content)
+
+
+class OpenAPIExtractorTest(unittest.TestCase):
+    def setUp(self):
+        self.dir = Path(tempfile.mkdtemp(prefix="modelgen-openapi-"))
+        self.spec = self.dir / "zoo.json"
+        self.spec.write_text(json.dumps(SPEC))
+        self.extractor = OpenAPIExtractor(self.spec)
+
+    def tearDown(self):
+        shutil.rmtree(self.dir, ignore_errors=True)
+
+    def test_detects_a_spec(self):
+        self.assertTrue(self.extractor.detect())
+
+    def test_does_not_detect_arbitrary_json(self):
+        other = self.dir / "not-a-spec.json"
+        other.write_text('{"hello": "world"}')
+        self.assertFalse(OpenAPIExtractor(other).detect())
+
+    def test_extracts_every_object_schema(self):
+        models, _ = self.extractor.extract()
+        self.assertEqual({m.name for m in models}, {"Pet", "Category", "PetPage"})
+
+    def test_enum_becomes_a_real_enum_class(self):
+        models, enums = self.extractor.extract()
+        # A materialised Enum is what makes every generator resolve it by name
+        # instead of falling through to str.
+        self.assertEqual([e.name for e in enums], ["PetStatus"])
+        status = next(f for f in models[0].fields if f.name == "status")
+        self.assertTrue(isinstance(status.type_hint, type))
+        self.assertTrue(issubclass(status.type_hint, Enum))
+        self.assertEqual([m.value for m in status.type_hint], ["available", "sold"])
+
+    def test_required_and_format_and_relations(self):
+        models, _ = self.extractor.extract()
+        fields = {f.name: f for f in next(m for m in models if m.name == "Pet").fields}
+
+        self.assertEqual(fields["id"].type_hint, "bigint")
+        self.assertTrue(fields["id"].primary_key)
+        self.assertFalse(fields["name"].optional)
+        self.assertTrue(fields["weight"].optional)
+        self.assertEqual(fields["born_on"].type_hint, "datetime")
+
+        self.assertEqual(fields["category"].foreign_key, "Category")
+        self.assertFalse(fields["category"].many)
+        self.assertEqual(fields["tags"].foreign_key, "Category")
+        self.assertTrue(fields["tags"].many)
+
+    def test_endpoints_carry_operation_shape(self):
+        by_id = {e.operation_id: e for e in self.extractor.endpoints()}
+        self.assertEqual(set(by_id), {"listPets", "createPet", "getPet"})
+
+        listing = by_id["listPets"]
+        self.assertEqual(listing.kind, "collection")
+        self.assertEqual(listing.response_model, "Pet")
+        self.assertTrue(listing.response_is_list)
+        # PetPage wraps the array, so a client expects {"items": [...]}.
+        self.assertEqual(listing.envelope_key, "items")
+
+        created = by_id["createPet"]
+        self.assertEqual(created.status, 201)
+        self.assertEqual(created.request_model, "Pet")
+
+        item = by_id["getPet"]
+        self.assertEqual(item.kind, "item")
+        self.assertEqual(item.path_params, ["petId"])
+        self.assertEqual(item.example, {"id": 7, "name": "Rocinante"})
+
+    def test_relations_reach_the_graphgen_schema(self):
+        out = self.dir / "schema.json"
+        GENERATORS["schema"]().generate(self.extractor.extract(), out)
+        schema = json.loads(out.read_text())["models"]
+        self.assertEqual(schema["Pet"]["fields"]["category"]["type"], "FK:Category")
+        self.assertEqual(schema["Pet"]["fields"]["tags"]["type"], "M2M:Category")
+
+
+class TabularExtractorTest(unittest.TestCase):
+    def setUp(self):
+        self.dir = Path(tempfile.mkdtemp(prefix="modelgen-tabular-"))
+        self.sheets = self.dir / "sheets"
+        self.sheets.mkdir()
+        (self.sheets / "customers.csv").write_text(CUSTOMERS_CSV)
+        (self.sheets / "orders.csv").write_text(ORDERS_CSV)
+        write_ods(
+            self.sheets / "line_items.ods",
+            "line_items",
+            [
+                ["line_id", "order_id", "sku", "qty", "note"],
+                ["1", "1001", "A-1", "2", "rush"],
+                ["2", "1001", "B-2", "1", ""],
+                ["3", "1002", "A-1", "5", ""],
+            ],
+        )
+        self.extractor = TabularExtractor(self.sheets)
+
+    def tearDown(self):
+        shutil.rmtree(self.dir, ignore_errors=True)
+
+    def test_detects_a_sheet_directory(self):
+        self.assertTrue(self.extractor.detect())
+        empty = self.dir / "empty"
+        empty.mkdir()
+        self.assertFalse(TabularExtractor(empty).detect())
+
+    def test_one_model_per_file_and_sheet(self):
+        models, _ = self.extractor.extract()
+        self.assertEqual(
+            {m.name for m in models}, {"Customers", "Orders", "LineItems"}
+        )
+
+    def test_types_are_inferred_per_column(self):
+        models, _ = self.extractor.extract()
+        fields = {
+            f.name: f for f in next(m for m in models if m.name == "Customers").fields
+        }
+        self.assertEqual(fields["id"].type_hint, int)
+        self.assertEqual(fields["name"].type_hint, str)
+        self.assertEqual(fields["active"].type_hint, bool)
+        self.assertEqual(fields["joined"].type_hint, "datetime")
+        self.assertEqual(fields["balance"].type_hint, float)
+        # One blank cell is what makes the column nullable.
+        self.assertTrue(fields["balance"].optional)
+        self.assertFalse(fields["name"].optional)
+
+    def test_keys_are_confirmed_against_the_data(self):
+        models, _ = self.extractor.extract()
+        by_name = {m.name: m for m in models}
+
+        customers = {f.name: f for f in by_name["Customers"].fields}
+        self.assertTrue(customers["id"].primary_key)
+
+        orders = {f.name: f for f in by_name["Orders"].fields}
+        self.assertTrue(orders["order_id"].primary_key)
+        # customer_id names another sheet, so it is a relation, not a key.
+        self.assertFalse(orders["customer_id"].primary_key)
+        self.assertEqual(orders["customer_id"].foreign_key, "Customers")
+
+    def test_ods_is_read_and_padding_ignored(self):
+        models, _ = self.extractor.extract()
+        line_items = next(m for m in models if m.name == "LineItems")
+        # Five real columns, not the 1023 the padding claims.
+        self.assertEqual([f.name for f in line_items.fields],
+                         ["line_id", "order_id", "sku", "qty", "note"])
+        fields = {f.name: f for f in line_items.fields}
+        self.assertEqual(fields["qty"].type_hint, int)
+        self.assertTrue(fields["note"].optional)
+        # line_id names the row rather than the sheet, but leads and holds.
+        self.assertTrue(fields["line_id"].primary_key)
+        self.assertEqual(fields["order_id"].foreign_key, "Orders")
+
+    def test_rows_are_kept_and_coerced(self):
+        self.extractor.extract()
+        datasets = {d.model: d for d in self.extractor.datasets()}
+        self.assertEqual(datasets["Customers"].collection, "customers")
+
+        rows = datasets["Customers"].rows
+        self.assertEqual(len(rows), 3)
+        self.assertEqual(rows[0]["id"], 1)
+        self.assertIs(rows[0]["active"], True)
+        self.assertEqual(rows[0]["balance"], 150.5)
+        # A blank cell is null, not the empty string.
+        self.assertIsNone(rows[2]["balance"])
+        self.assertEqual(datasets["LineItems"].rows[1]["note"], None)
+
+
+class DatagenTargetTest(unittest.TestCase):
+    def setUp(self):
+        self.dir = Path(tempfile.mkdtemp(prefix="modelgen-datagen-"))
+        self.sheets = self.dir / "sheets"
+        self.sheets.mkdir()
+        (self.sheets / "customers.csv").write_text(CUSTOMERS_CSV)
+
+    def tearDown(self):
+        shutil.rmtree(self.dir, ignore_errors=True)
+
+    def _generate(self, seeded: bool):
+        extractor = TabularExtractor(self.sheets)
+        models, enums = extractor.extract()
+        datasets = extractor.datasets() if seeded else []
+
+        out = self.dir / "gen" / "datagen_demo.py"
+        DatagenGenerator(class_name="DemoGenerator").generate(
+            (models, enums, datasets), out
+        )
+        if seeded:
+            depot = out.parent / "depot"
+            depot.mkdir(exist_ok=True)
+            (depot / "data.json").write_text(
+                json.dumps({d.model: d.rows for d in datasets})
+            )
+
+        import importlib.util
+
+        spec = importlib.util.spec_from_file_location(f"demo_{seeded}", out)
+        module = importlib.util.module_from_spec(spec)
+        spec.loader.exec_module(module)
+        return module.DemoGenerator()
+
+    def test_registered_as_a_target(self):
+        self.assertIn("datagen", GENERATORS)
+
+    def test_synthesises_when_there_are_no_rows(self):
+        generator = self._generate(seeded=False)
+        self.assertEqual(generator.available_models(), ["customers"])
+
+        record = generator.generate("Customers", 1)[0]
+        self.assertEqual(
+            set(record), {"id", "name", "email", "active", "joined", "balance"}
+        )
+        self.assertIsInstance(record["id"], int)
+        self.assertIsInstance(record["active"], bool)
+        self.assertIn("@", record["email"])
+
+    def test_samples_real_rows_when_seeded(self):
+        generator = self._generate(seeded=True)
+        names = {generator.generate("Customers", 1)[0]["name"] for _ in range(25)}
+        self.assertTrue(names <= {"Ada", "Bruno", "Camila"}, names)
+
+    def test_kwargs_override_the_result(self):
+        generator = self._generate(seeded=True)
+        self.assertEqual(generator.generate("Customers", 1, name="Zed")[0]["name"], "Zed")
+
+    def test_exposes_a_graphgen_schema(self):
+        schema = self._generate(seeded=False).schema()
+        self.assertIn("Customers", schema["models"])
+        self.assertTrue(schema["models"]["Customers"]["fields"]["id"]["pk"])
+
+    def test_unknown_model_is_reported(self):
+        generator = self._generate(seeded=False)
+        with self.assertRaises(ValueError):
+            generator.generate("Nope", 1)
+
+
+if __name__ == "__main__":
+    unittest.main()
diff --git a/soleprint/station/tools/modelgen/types.py b/soleprint/station/tools/modelgen/types.py
index 274d14a..5187feb 100644
--- a/soleprint/station/tools/modelgen/types.py
+++ b/soleprint/station/tools/modelgen/types.py
@@ -61,6 +61,11 @@ PYDANTIC_RESOLVERS: dict[Any, Callable[[Any], str]] = {
     "list": lambda base: f"List[{_get_list_inner(base)}]",
     "enum": lambda base: base.__name__,
     "dataclass": lambda base: base.__name__,
+    # DB- and spec-shaped hints. Without these an int64 column resolves through
+    # the "unknown -> str" fallback and a BigIntegerField arrives as a string.
+    "bigint": lambda _: "int",
+    "text": lambda _: "str",
+    "bytes": lambda _: "bytes",
 }
 
 # =============================================================================
@@ -95,6 +100,11 @@ TS_RESOLVERS: dict[Any, Callable[[Any], str]] = {
     "list": _resolve_ts_list,
     "enum": lambda base: base.__name__,
     "dataclass": lambda base: base.__name__,
+    # JS has no 64-bit integer literal type, so int64 is a number like any
+    # other; text is a string; binary arrives base64-encoded over JSON.
+    "bigint": lambda _: "number",
+    "text": lambda _: "string",
+    "bytes": lambda _: "string",
 }
 
 # =============================================================================
diff --git a/soleprint/station/tools/shuntgen/README.md b/soleprint/station/tools/shuntgen/README.md
new file mode 100644
index 0000000..80f8002
--- /dev/null
+++ b/soleprint/station/tools/shuntgen/README.md
@@ -0,0 +1,127 @@
+# shuntgen
+
+Generates runnable [shunts](../../../artery/shunts/) from the two things people
+actually have: a service contract, or a folder of spreadsheets.
+
+```bash
+# a spec you were handed
+python -m station.tools.shuntgen from-openapi -s api.yaml -o artery/shunts/petstore
+
+# sheets a client sent
+python -m station.tools.shuntgen from-tabular -s ./sheets -o artery/shunts/books
+
+python -m station.tools.shuntgen list
+```
+
+Run from `soleprint/`, so `station.tools...` resolves. Also available in the
+browser at `/station/tools/shuntgen/`.
+
+## What comes out
+
+```
+artery/shunts/<name>/
+  main.py               builds the app from the spec
+  run.py                uvicorn entry point (PORT, or depot/config.json)
+  shunt_runtime.py      vendored copy of runtime.py
+  models.py             pydantic, via modelgen
+  datagen_<name>.py     BaseDataGenerator subclass, via modelgen
+  depot/spec.json       routes, collections and schema
+  depot/responses.json  pinned overrides — yours, never overwritten
+  depot/config.json     delays, error rate, prefill — yours, never overwritten
+  depot/data.json       imported rows
+  templates/index.html  config UI
+  README.md
+```
+
+```bash
+cd artery/shunts/books && python run.py
+curl localhost:8098/customers
+```
+
+## Where a response comes from
+
+First hit wins:
+
+1. `depot/responses.json` — a pinned override, keyed `"METHOD /path"`
+2. the store — rows imported from sheets, plus anything POSTed since
+3. the spec's `example`, if the source document carried one
+4. `datagen_<name>.py`, synthesising from the schema
+5. `{}`
+
+The store is the part that makes it behave like a service: POST something and
+GET it back, ask for `/pets/7` and get the pet whose id is 7. Collections with
+no imported rows are prefilled with generated ones (`prefill` in
+`depot/config.json`) so the first call answers with something.
+
+## Two sources, one pipeline
+
+Both inputs are modelgen extractors, so the same shapes also generate pydantic,
+TypeScript, prisma and a graphgen schema:
+
+```bash
+python -m station.tools.modelgen from-openapi -s api.yaml -o out/ -t pydantic,typescript
+python -m station.tools.modelgen from-tabular -s ./sheets -o out/ -t schema,datagen
+```
+
+| Source | Becomes | Routes |
+| --- | --- | --- |
+| OpenAPI 3.x / Swagger 2.0 | one model per schema, enums as real Enums, `$ref` as relations | the operations the document declares |
+| `.csv` / `.tsv` / `.ods` | one model per file or sheet, types inferred per column | five CRUD routes per table |
+
+Keys and relations are inferred and then checked against the data: an `id`
+column that is not unique is not treated as a key, and `customer_id` is only a
+foreign key if a `customers` sheet came with it.
+
+ODS is read with `zipfile` + `ElementTree` — no odfpy, no pandas — which is what
+lets modelgen stay dependency-free and publishable on its own.
+
+## Control endpoints
+
+Every generated shunt serves these:
+
+| Endpoint | Purpose |
+| --- | --- |
+| `GET /health` | liveness |
+| `GET /mock/spec` | the routes it was built from |
+| `GET /mock/stats` | call counts and row counts |
+| `POST /mock/reset` | restore imported rows, clear counters |
+| `GET,POST /mock/config` | delays, error rate, `unknown_id`, page size |
+| `GET,POST /mock/responses` | pin an override; set a key to `null` to drop it |
+
+```bash
+# make it slow and flaky, the way the real thing is
+curl -X POST localhost:8098/mock/config \
+  -H 'content-type: application/json' \
+  -d '{"enable_random_delays": true, "error_rate": 0.2}'
+
+# make one call answer something specific
+curl -X POST localhost:8098/mock/responses \
+  -H 'content-type: application/json' \
+  -d '{"GET /customers/1": {"id": 1, "name": "PINNED"}}'
+```
+
+`unknown_id` decides what an unknown key does: `generate` (the default) invents
+a record wearing the id that was asked for, `404` refuses it. Generate by
+default because a client pointed at a fresh shunt should just work; flip it when
+the error path is what you are testing.
+
+## Dependency containers
+
+`--cabinet postgres,redis` writes a `cabinet.json` declaring what the shunt
+expects. `python build.py --cfg <room>` composes those services into the room's
+`docker-compose.yml`; on a cluster they install as rig addons of the same name.
+See [cabinets](../../cabinets/README.md).
+
+## Regenerating
+
+Everything is overwritten except `depot/responses.json` and `depot/config.json`.
+Fixing a bug in `runtime.py` and regenerating fixes it in every shunt, which is
+why the routes are built from `spec.json` at startup rather than written out as
+source.
+
+## Fixtures
+
+`fixtures/petstore.yaml` and `fixtures/sheets/` exercise the shapes that are
+easy to get wrong — an enum, a `$ref`, an array of `$ref`, a wrapped collection,
+a path parameter, an ODS sheet with padding and a blank column, and a foreign
+key across two files.
diff --git a/soleprint/station/tools/shuntgen/__init__.py b/soleprint/station/tools/shuntgen/__init__.py
new file mode 100644
index 0000000..669d239
--- /dev/null
+++ b/soleprint/station/tools/shuntgen/__init__.py
@@ -0,0 +1,29 @@
+"""
+Shuntgen - Generate runnable shunts from a service contract or a pile of sheets.
+
+A shunt is artery's fake connector: a stand-in service that answers like the
+real one so tests can run without it. Writing one by hand means copying
+artery/shunts/example/ and filling in responses.json by hand, which is fine for
+three endpoints and untenable for eighty.
+
+This tool takes the two things people actually have —
+
+    an OpenAPI/Swagger document        the service already exists somewhere
+    a directory of CSV/ODS sheets      the data exists, the service does not
+
+— and emits a shunt that runs: typed models, a data generator, seeded routes,
+and a config UI.
+
+Both inputs reach modelgen's IR through its own extractors, so the shapes also
+generate pydantic, TypeScript, prisma and a graphgen schema for free. This
+package only adds the emitter.
+
+    python -m station.tools.shuntgen from-openapi -s api.yaml -o artery/shunts/petstore
+    python -m station.tools.shuntgen from-tabular -s ./sheets  -o artery/shunts/books
+"""
+
+from .emit import ShuntEmitter
+
+__version__ = "0.1.0"
+
+__all__ = ["ShuntEmitter"]
diff --git a/soleprint/station/tools/shuntgen/__main__.py b/soleprint/station/tools/shuntgen/__main__.py
new file mode 100644
index 0000000..24fb0bc
--- /dev/null
+++ b/soleprint/station/tools/shuntgen/__main__.py
@@ -0,0 +1,239 @@
+"""
+Shuntgen CLI.
+
+    python -m station.tools.shuntgen from-openapi -s api.yaml -o artery/shunts/petstore
+    python -m station.tools.shuntgen from-tabular -s ./sheets -o artery/shunts/books
+    python -m station.tools.shuntgen list
+
+Run from the soleprint/ directory so `station.tools...` resolves.
+"""
+
+import argparse
+import sys
+from pathlib import Path
+
+from .emit import SPR_ROOT, ShuntEmitter
+
+
+def _name_for(args, source: Path) -> str:
+    """The shunt's name: given, else the output folder, else the source."""
+    if getattr(args, "name", None):
+        return args.name
+    output = Path(args.output)
+    if output.name and output.name not in (".", ".."):
+        return output.name
+    return source.stem
+
+
+def _refuse_to_clobber(output: Path, force: bool) -> None:
+    """Regenerating is fine; overwriting something that is not a shunt is not."""
+    if not output.exists() or force:
+        return
+    if not any(output.iterdir()):
+        return
+    if (output / "depot" / "spec.json").exists():
+        return
+    print(
+        f"Error: {output} already exists and was not generated by shuntgen.\n"
+        "       Pick another path, or pass --force to write into it anyway.",
+        file=sys.stderr,
+    )
+    sys.exit(1)
+
+
+def cmd_from_openapi(args):
+    """Build a shunt from an OpenAPI 3.x / Swagger 2.0 document."""
+    from ..modelgen.loader.extract.openapi import OpenAPIExtractor
+
+    spec_path = Path(args.spec)
+    if not spec_path.exists():
+        print(f"Error: Spec not found: {spec_path}", file=sys.stderr)
+        sys.exit(1)
+
+    output = Path(args.output)
+    _refuse_to_clobber(output, args.force)
+
+    extractor = OpenAPIExtractor(spec_path)
+    print(f"Reading spec: {spec_path}")
+    try:
+        models, enums = extractor.extract()
+        endpoints = extractor.endpoints()
+    except (RuntimeError, ValueError) as e:
+        print(f"Error: {e}", file=sys.stderr)
+        sys.exit(1)
+
+    if not endpoints:
+        print(
+            "Error: the spec declares no operations, so there is nothing to serve.",
+            file=sys.stderr,
+        )
+        sys.exit(1)
+
+    name = _name_for(args, spec_path)
+    print(f"Found {len(models)} models, {len(endpoints)} endpoints")
+
+    written = ShuntEmitter(
+        name=name,
+        output=output,
+        models=models,
+        enums=enums,
+        endpoints=endpoints,
+        title=args.title,
+        source=spec_path.name,
+        kind="openapi",
+        port=args.port,
+        cabinets=_cabinets(args),
+    ).emit()
+
+    _report(written, name, args.port)
+
+
+def cmd_from_tabular(args):
+    """Build a shunt from a directory of CSV/TSV/ODS sheets."""
+    from ..modelgen.loader.extract.tabular import TabularExtractor
+
+    source_path = Path(args.source)
+    if not source_path.exists():
+        print(f"Error: Source not found: {source_path}", file=sys.stderr)
+        sys.exit(1)
+
+    output = Path(args.output)
+    _refuse_to_clobber(output, args.force)
+
+    extractor = TabularExtractor(source_path)
+    print(f"Reading sheets: {source_path}")
+    try:
+        models, enums = extractor.extract()
+    except ValueError as e:
+        print(f"Error: {e}", file=sys.stderr)
+        sys.exit(1)
+
+    datasets = extractor.datasets()
+    rows = sum(len(d.rows) for d in datasets)
+    name = _name_for(args, source_path)
+    print(f"Found {len(models)} models, {rows} rows")
+
+    written = ShuntEmitter(
+        name=name,
+        output=output,
+        models=models,
+        enums=enums,
+        datasets=datasets,
+        title=args.title,
+        source=source_path.name,
+        kind="tabular",
+        port=args.port,
+        cabinets=_cabinets(args),
+    ).emit()
+
+    _report(written, name, args.port)
+
+
+def cmd_list(args):
+    """List the shunts that exist under artery/shunts/."""
+    shunts_dir = SPR_ROOT / "artery" / "shunts"
+    if not shunts_dir.exists():
+        print(f"No shunts directory at {shunts_dir}")
+        return
+
+    found = False
+    for path in sorted(shunts_dir.iterdir()):
+        if not path.is_dir() or path.name.startswith(("_", ".")):
+            continue
+        found = True
+        spec = path / "depot" / "spec.json"
+        if spec.exists():
+            import json
+
+            try:
+                data = json.loads(spec.read_text())
+                print(
+                    f"  {path.name:<20} generated  "
+                    f"{len(data.get('routes', []))} routes from {data.get('source', '?')}"
+                )
+                continue
+            except (OSError, ValueError):
+                pass
+        print(f"  {path.name:<20} hand-written")
+
+    if not found:
+        print("  (none)")
+
+
+def _cabinets(args) -> list:
+    if not getattr(args, "cabinet", None):
+        return []
+    return [c.strip() for c in args.cabinet.split(",") if c.strip()]
+
+
+def _report(output: Path, name: str, port: int) -> None:
+    print(f"\nWrote {output}")
+    print("\nRun it:")
+    print(f"    cd {output} && python run.py")
+    print(f"    curl localhost:{port}/health")
+    print(f"    open http://localhost:{port}/")
+
+
+def _add_common(parser, port_default: int) -> None:
+    parser.add_argument(
+        "--output", "-o", type=str, required=True,
+        help="Where to write the shunt (e.g. artery/shunts/petstore)",
+    )
+    parser.add_argument(
+        "--name", "-n", type=str, default=None,
+        help="Shunt name (default: the output folder's name)",
+    )
+    parser.add_argument(
+        "--title", type=str, default=None,
+        help="Display title for the config UI (default: derived from the name)",
+    )
+    parser.add_argument(
+        "--port", "-p", type=int, default=port_default,
+        help=f"Default port for run.py (default: {port_default})",
+    )
+    parser.add_argument(
+        "--cabinet", type=str, default=None,
+        help="Comma-separated dependency containers to declare (e.g. postgres,redis)",
+    )
+    parser.add_argument(
+        "--force", action="store_true",
+        help="Write into a non-empty directory that shuntgen did not generate",
+    )
+
+
+def main():
+    parser = argparse.ArgumentParser(
+        description="Shuntgen - generate runnable shunts",
+        formatter_class=argparse.RawDescriptionHelpFormatter,
+    )
+    subparsers = parser.add_subparsers(dest="command", required=True)
+
+    openapi_parser = subparsers.add_parser(
+        "from-openapi", help="Generate a shunt from an OpenAPI / Swagger document"
+    )
+    openapi_parser.add_argument(
+        "--spec", "-s", type=str, required=True,
+        help="Path to the spec (.json, .yaml or .yml)",
+    )
+    _add_common(openapi_parser, 8099)
+    openapi_parser.set_defaults(func=cmd_from_openapi)
+
+    tabular_parser = subparsers.add_parser(
+        "from-tabular", help="Generate a shunt from a directory of CSV/TSV/ODS sheets"
+    )
+    tabular_parser.add_argument(
+        "--source", "-s", type=str, required=True,
+        help="Directory of sheets (or a single .csv/.tsv/.ods file)",
+    )
+    _add_common(tabular_parser, 8098)
+    tabular_parser.set_defaults(func=cmd_from_tabular)
+
+    list_parser = subparsers.add_parser("list", help="List shunts under artery/shunts/")
+    list_parser.set_defaults(func=cmd_list)
+
+    args = parser.parse_args()
+    args.func(args)
+
+
+if __name__ == "__main__":
+    main()
diff --git a/soleprint/station/tools/shuntgen/api.py b/soleprint/station/tools/shuntgen/api.py
new file mode 100644
index 0000000..a8f4624
--- /dev/null
+++ b/soleprint/station/tools/shuntgen/api.py
@@ -0,0 +1,354 @@
+"""FastAPI router for shuntgen — generate shunts from a spec or a sheet folder.
+
+Mounted by run.py under /station, so the routes below live at
+/station/tools/shuntgen/... , the same shape as datagen and graphgen.
+
+Generation writes files, so every path is resolved against the soleprint tree
+and anything pointing outside it is refused. A tool that turns an uploaded file
+into a directory of Python is not somewhere to be relaxed about paths.
+"""
+
+import json
+import logging
+import shutil
+import tempfile
+from pathlib import Path
+from typing import Any, Optional
+
+from fastapi import APIRouter, HTTPException, UploadFile
+from fastapi.responses import HTMLResponse
+from pydantic import BaseModel
+
+from .emit import SPR_ROOT, ShuntEmitter
+
+log = logging.getLogger(__name__)
+router = APIRouter(prefix="/tools/shuntgen", tags=["shuntgen"])
+
+SHUNTS_DIR = SPR_ROOT / "artery" / "shunts"
+UPLOAD_DIR = SPR_ROOT / "station" / "tools" / "shuntgen" / "uploads"
+
+# Room for a large spec, a hard stop well short of anything that would exhaust
+# memory while being parsed.
+MAX_UPLOAD_BYTES = 8 * 1024 * 1024
+
+
+# ─────────────────────────────────────────────────────
+# Path safety
+# ─────────────────────────────────────────────────────
+
+
+def _inside(path: Path, root: Path) -> Path:
+    """Resolve a path and refuse it if it escapes root."""
+    resolved = (root / path).resolve() if not path.is_absolute() else path.resolve()
+    try:
+        resolved.relative_to(root.resolve())
+    except ValueError:
+        raise HTTPException(
+            status_code=400,
+            detail=f"Path must stay inside {root.name}/: {path}",
+        )
+    return resolved
+
+
+def _safe_name(name: str) -> str:
+    cleaned = "".join(c for c in name if c.isalnum() or c in "-_").strip("-_")
+    if not cleaned:
+        raise HTTPException(status_code=400, detail="Name must contain letters or digits")
+    return cleaned.lower()
+
+
+# ─────────────────────────────────────────────────────
+# Models
+# ─────────────────────────────────────────────────────
+
+
+class GenerateRequest(BaseModel):
+    name: str
+    source: str  # spec file or sheet directory, relative to soleprint/
+    kind: str = "auto"  # "openapi" | "tabular" | "auto"
+    title: Optional[str] = None
+    port: int = 8099
+    cabinets: list[str] = []
+    force: bool = False
+
+
+# ─────────────────────────────────────────────────────
+# Routes
+# ─────────────────────────────────────────────────────
+
+
+@router.get("/", response_class=HTMLResponse)
+def index():
+    html = Path(__file__).parent / "templates" / "index.html"
+    return HTMLResponse(html.read_text() if html.exists() else "<h1>shuntgen</h1>")
+
+
+@router.get("/health")
+def health():
+    return {"status": "ok", "tool": "shuntgen"}
+
+
+@router.get("/api/shunts")
+def list_shunts():
+    """Every shunt under artery/shunts/, generated or hand-written."""
+    out = []
+    if SHUNTS_DIR.exists():
+        for path in sorted(SHUNTS_DIR.iterdir()):
+            if not path.is_dir() or path.name.startswith(("_", ".")):
+                continue
+            entry: dict[str, Any] = {"name": path.name, "generated": False}
+            spec_file = path / "depot" / "spec.json"
+            if spec_file.exists():
+                try:
+                    spec = json.loads(spec_file.read_text())
+                    entry.update(
+                        generated=True,
+                        title=spec.get("title"),
+                        kind=spec.get("kind"),
+                        source=spec.get("source"),
+                        routes=len(spec.get("routes", [])),
+                        models=len(spec.get("models", {})),
+                    )
+                except (OSError, ValueError) as e:
+                    entry["error"] = str(e)
+            out.append(entry)
+    return {"shunts": out}
+
+
+@router.get("/api/sources")
+def list_sources():
+    """Candidate inputs: uploaded specs, and sheet folders under uploads/."""
+    specs, sheets = [], []
+    if UPLOAD_DIR.exists():
+        for path in sorted(UPLOAD_DIR.rglob("*")):
+            rel = str(path.relative_to(SPR_ROOT))
+            if path.is_file() and path.suffix.lower() in (".json", ".yaml", ".yml"):
+                specs.append(rel)
+            elif path.is_dir() and any(
+                child.suffix.lower() in (".csv", ".tsv", ".ods")
+                for child in path.iterdir()
+                if child.is_file()
+            ):
+                sheets.append(rel)
+
+    fixtures = Path("station/tools/shuntgen/fixtures")
+    if (SPR_ROOT / fixtures).exists():
+        specs.append(str(fixtures / "petstore.yaml"))
+        sheets.append(str(fixtures / "sheets"))
+
+    return {"specs": specs, "sheets": sheets}
+
+
+def _multipart_available() -> bool:
+    """Whether FastAPI can accept file uploads in this environment.
+
+    Declaring an UploadFile parameter without python-multipart raises at import
+    time, not request time. Registering it unconditionally would mean one
+    missing optional dependency stops the whole tool from loading — so the
+    route is registered only when it can work, and a stub explains its absence.
+    """
+    try:
+        import multipart  # noqa: F401
+
+        return True
+    except ImportError:
+        return False
+
+
+async def _upload(file: UploadFile, folder: str = ""):
+    """Accept a spec or sheet, into uploads/[folder]/."""
+    if not file.filename:
+        raise HTTPException(status_code=400, detail="No filename")
+
+    suffix = Path(file.filename).suffix.lower()
+    if suffix not in (".json", ".yaml", ".yml", ".csv", ".tsv", ".ods"):
+        raise HTTPException(
+            status_code=400,
+            detail=f"Unsupported file type '{suffix}'. "
+            "Expected a spec (.json/.yaml/.yml) or a sheet (.csv/.tsv/.ods).",
+        )
+
+    payload = await file.read()
+    if len(payload) > MAX_UPLOAD_BYTES:
+        raise HTTPException(
+            status_code=413,
+            detail=f"File is larger than {MAX_UPLOAD_BYTES // (1024 * 1024)}MB",
+        )
+
+    target_dir = UPLOAD_DIR
+    if folder:
+        target_dir = _inside(Path("station/tools/shuntgen/uploads") / _safe_name(folder), SPR_ROOT)
+    target_dir.mkdir(parents=True, exist_ok=True)
+
+    target = target_dir / Path(file.filename).name
+    target.write_bytes(payload)
+    return {"path": str(target.relative_to(SPR_ROOT)), "bytes": len(payload)}
+
+
+if _multipart_available():
+    router.add_api_route("/api/upload", _upload, methods=["POST"], name="upload")
+else:
+
+    @router.post("/api/upload")
+    def upload_unavailable():
+        raise HTTPException(
+            status_code=501,
+            detail="Uploads need python-multipart. Install it, or point "
+            "'source' at a path on disk — generation itself works either way.",
+        )
+
+
+@router.post("/api/generate")
+def generate(req: GenerateRequest):
+    """Generate a shunt into artery/shunts/<name>/."""
+    name = _safe_name(req.name)
+    source = _inside(Path(req.source), SPR_ROOT)
+    if not source.exists():
+        raise HTTPException(status_code=404, detail=f"Source not found: {req.source}")
+
+    output = _inside(Path("artery/shunts") / name, SPR_ROOT)
+    if (
+        output.exists()
+        and any(output.iterdir())
+        and not (output / "depot" / "spec.json").exists()
+        and not req.force
+    ):
+        raise HTTPException(
+            status_code=409,
+            detail=f"artery/shunts/{name} exists and was not generated by shuntgen. "
+            "Pass force to write into it anyway.",
+        )
+
+    kind = req.kind
+    if kind == "auto":
+        kind = "tabular" if source.is_dir() else "openapi"
+
+    try:
+        if kind == "openapi":
+            from ..modelgen.loader.extract.openapi import OpenAPIExtractor
+
+            extractor = OpenAPIExtractor(source)
+            models, enums = extractor.extract()
+            endpoints = extractor.endpoints()
+            datasets = []
+            if not endpoints:
+                raise HTTPException(
+                    status_code=400,
+                    detail="The spec declares no operations, so there is nothing to serve.",
+                )
+        elif kind == "tabular":
+            from ..modelgen.loader.extract.tabular import TabularExtractor
+
+            extractor = TabularExtractor(source)
+            models, enums = extractor.extract()
+            datasets = extractor.datasets()
+            endpoints = []
+        else:
+            raise HTTPException(status_code=400, detail=f"Unknown kind: {req.kind}")
+    except HTTPException:
+        raise
+    except (RuntimeError, ValueError) as e:
+        raise HTTPException(status_code=400, detail=str(e))
+    except Exception as e:
+        log.exception("shuntgen: extraction failed")
+        raise HTTPException(status_code=500, detail=str(e))
+
+    try:
+        written = ShuntEmitter(
+            name=name,
+            output=output,
+            models=models,
+            enums=enums,
+            datasets=datasets,
+            endpoints=endpoints,
+            title=req.title,
+            source=source.name,
+            kind=kind,
+            port=req.port,
+            cabinets=req.cabinets,
+        ).emit()
+    except Exception as e:
+        log.exception("shuntgen: emission failed")
+        raise HTTPException(status_code=500, detail=str(e))
+
+    spec = json.loads((written / "depot" / "spec.json").read_text())
+    return {
+        "name": name,
+        "path": str(written.relative_to(SPR_ROOT)),
+        "kind": kind,
+        "models": len(models),
+        "routes": len(spec.get("routes", [])),
+        "rows": sum(len(d.rows) for d in datasets),
+        "run": f"cd {written.relative_to(SPR_ROOT)} && python run.py",
+    }
+
+
+@router.post("/api/preview")
+def preview(req: GenerateRequest):
+    """Extract and report what would be generated, writing nothing permanent."""
+    source = _inside(Path(req.source), SPR_ROOT)
+    if not source.exists():
+        raise HTTPException(status_code=404, detail=f"Source not found: {req.source}")
+
+    kind = req.kind
+    if kind == "auto":
+        kind = "tabular" if source.is_dir() else "openapi"
+
+    try:
+        if kind == "openapi":
+            from ..modelgen.loader.extract.openapi import OpenAPIExtractor
+
+            extractor = OpenAPIExtractor(source)
+            models, enums = extractor.extract()
+            endpoints, datasets = extractor.endpoints(), []
+        else:
+            from ..modelgen.loader.extract.tabular import TabularExtractor
+
+            extractor = TabularExtractor(source)
+            models, enums = extractor.extract()
+            datasets, endpoints = extractor.datasets(), []
+    except (RuntimeError, ValueError) as e:
+        raise HTTPException(status_code=400, detail=str(e))
+
+    # Emit into a throwaway directory: the routes are worked out by the emitter,
+    # and duplicating that logic here is how a preview drifts from the thing it
+    # is previewing.
+    temp = Path(tempfile.mkdtemp(prefix="shuntgen-preview-"))
+    try:
+        emitter = ShuntEmitter(
+            name=_safe_name(req.name or "preview"),
+            output=temp,
+            models=models,
+            enums=enums,
+            datasets=datasets,
+            endpoints=endpoints,
+            source=source.name,
+            kind=kind,
+        )
+        collections = emitter._collections()
+        routes = emitter._routes(collections)
+    finally:
+        shutil.rmtree(temp, ignore_errors=True)
+
+    return {
+        "kind": kind,
+        "models": [
+            {
+                "name": m.name,
+                "fields": len(m.fields),
+                "doc": (m.docstring or "").strip().splitlines()[0] if m.docstring else None,
+            }
+            for m in models
+        ],
+        "collections": collections,
+        "routes": [
+            {
+                "method": r["method"],
+                "path": r["path"],
+                "operation": r["operation"],
+                "model": r["model"],
+            }
+            for r in routes
+        ],
+        "rows": sum(len(d.rows) for d in datasets),
+    }
diff --git a/soleprint/station/tools/shuntgen/emit.py b/soleprint/station/tools/shuntgen/emit.py
new file mode 100644
index 0000000..070a997
--- /dev/null
+++ b/soleprint/station/tools/shuntgen/emit.py
@@ -0,0 +1,462 @@
+"""
+Shunt emission — turns extracted models into a runnable shunt directory.
+
+The layout follows the contract in artery/shunts/__init__.py (main.py, a depot,
+a README) and adds what a generated shunt needs to answer for itself:
+
+    artery/shunts/<name>/
+      main.py               builds the app from the spec
+      run.py                uvicorn entry point
+      shunt_runtime.py      vendored copy of runtime.py
+      models.py             pydantic, via modelgen
+      datagen_<name>.py     BaseDataGenerator subclass, via modelgen
+      depot/spec.json       normalised routes + collections + schema
+      depot/responses.json  pinned overrides, the "METHOD /path" map
+      depot/data.json       imported rows
+      depot/config.json     latency / error-injection knobs
+      templates/index.html  config UI
+      cabinet.json          declared dependency containers, if any
+      README.md
+
+Only spec.json and the depot are worth editing by hand; everything else is
+regenerated. The vendored runtime is a copy rather than an import because a
+shunt runs standalone, with no soleprint on its path.
+"""
+
+import json
+import shutil
+from pathlib import Path
+from typing import Any, Dict, List, Optional
+
+from ..modelgen.generator import DatagenGenerator, JsonSchemaGenerator, PydanticGenerator
+from ..modelgen.loader.schema import (
+    DatasetDefinition,
+    EndpointDefinition,
+    ModelDefinition,
+)
+
+HERE = Path(__file__).parent
+# soleprint/ — four levels up from station/tools/shuntgen/emit.py
+SPR_ROOT = HERE.parents[2]
+
+# Types whose keys are integers, so the runtime coerces "/pets/7" to 7 before
+# comparing it with a stored row.
+_INT_HINTS = {int, "bigint"}
+
+
+def _pk_of(model: ModelDefinition) -> tuple[Optional[str], str]:
+    """Return (primary key field name, "int" | "str") for a model."""
+    for field in model.fields:
+        if getattr(field, "primary_key", False):
+            return field.name, "int" if field.type_hint in _INT_HINTS else "str"
+    for field in model.fields:
+        if field.name == "id":
+            return field.name, "int" if field.type_hint in _INT_HINTS else "str"
+    return None, "str"
+
+
+def _operation(method: str, kind: str) -> str:
+    """Name what a route does, from its verb and whether it addresses one row."""
+    if method == "GET":
+        return "list" if kind == "collection" else "retrieve" if kind == "item" else "action"
+    if method == "POST":
+        return "create" if kind == "collection" else "action"
+    if method in ("PUT", "PATCH"):
+        return "update" if kind == "item" else "action"
+    if method == "DELETE":
+        return "delete" if kind == "item" else "action"
+    return "action"
+
+
+def _class_name(name: str) -> str:
+    parts = [p for p in name.replace("-", "_").split("_") if p]
+    return "".join(p[:1].upper() + p[1:] for p in parts) or "Shunt"
+
+
+def _theme_css() -> str:
+    """The theme, inlined.
+
+    A shunt serves its own UI on its own port, so it cannot fetch soleprint's
+    /theme.css. Inlining keeps it standalone and keeps one source of truth —
+    regenerating picks up any change to common/theme.
+    """
+    theme_dir = SPR_ROOT / "common" / "theme"
+    parts: List[str] = []
+    tokens = theme_dir / "tokens.css"
+    if tokens.exists():
+        parts.append(tokens.read_text())
+    for sheet in sorted((theme_dir / "themes").glob("*.css")):
+        parts.append(sheet.read_text())
+    if parts:
+        return "\n".join(parts)
+    return ":root{--bg:#0a0a0a;--surface:#1a1a1a;--border:#333;--text:#e5e5e5;--muted:#a3a3a3;--accent:#d4a574}"
+
+
+class ShuntEmitter:
+    """Writes a complete shunt directory."""
+
+    def __init__(
+        self,
+        name: str,
+        output: Path,
+        models: List[ModelDefinition],
+        enums: Optional[List[Any]] = None,
+        datasets: Optional[List[DatasetDefinition]] = None,
+        endpoints: Optional[List[EndpointDefinition]] = None,
+        title: Optional[str] = None,
+        source: str = "",
+        kind: str = "openapi",
+        port: int = 8099,
+        cabinets: Optional[List[str]] = None,
+    ):
+        self.name = name
+        self.output = Path(output)
+        self.models = models
+        self.enums = enums or []
+        self.datasets = datasets or []
+        self.endpoints = endpoints or []
+        self.title = title or _class_name(name)
+        self.source = source
+        self.kind = kind
+        self.port = port
+        self.cabinets = cabinets or []
+        self.by_name = {m.name: m for m in models}
+
+    # ── entry point ────────────────────────────────────────────────────────
+
+    def emit(self) -> Path:
+        self.output.mkdir(parents=True, exist_ok=True)
+        (self.output / "depot").mkdir(exist_ok=True)
+        (self.output / "templates").mkdir(exist_ok=True)
+
+        collections = self._collections()
+        routes = self._routes(collections)
+
+        self._write_models()
+        self._write_generator()
+        self._write_depot(routes, collections)
+        self._write_runtime()
+        self._write_app()
+        self._write_ui(routes)
+        self._write_cabinets()
+        self._write_readme(routes, collections)
+        return self.output
+
+    # ── spec construction ──────────────────────────────────────────────────
+
+    def _collections(self) -> Dict[str, dict]:
+        """Models the runtime may keep rows for, with the key to match them on."""
+        out: Dict[str, dict] = {}
+
+        for dataset in self.datasets:
+            model = self.by_name.get(dataset.model)
+            if not model:
+                continue
+            pk, pk_type = _pk_of(model)
+            out[dataset.model] = {
+                "path": f"/{dataset.collection or dataset.model.lower()}",
+                "pk": pk or "id",
+                "pk_type": pk_type,
+                "rows": len(dataset.rows),
+            }
+
+        # A spec's models get a collection too, so POSTing to one and GETting it
+        # back works even though no rows were imported.
+        for endpoint in self.endpoints:
+            model_name = endpoint.model
+            if not model_name or model_name in out:
+                continue
+            model = self.by_name.get(model_name)
+            if not model:
+                continue
+            pk, pk_type = _pk_of(model)
+            if not pk:
+                continue
+            out[model_name] = {
+                "path": self._base_path(endpoint.path),
+                "pk": pk,
+                "pk_type": pk_type,
+                "rows": 0,
+            }
+
+        return out
+
+    @staticmethod
+    def _base_path(path: str) -> str:
+        """Trim a path back to its collection — /pets/{petId} -> /pets."""
+        segments = [s for s in path.split("/") if s and not s.startswith("{")]
+        return "/" + "/".join(segments) if segments else "/"
+
+    def _routes(self, collections: Dict[str, dict]) -> List[dict]:
+        if self.endpoints:
+            return [self._from_endpoint(e) for e in self.endpoints]
+        return self._crud_routes(collections)
+
+    def _from_endpoint(self, endpoint: EndpointDefinition) -> dict:
+        return {
+            "method": endpoint.method,
+            "path": endpoint.path,
+            "operation_id": endpoint.operation_id,
+            "summary": endpoint.summary,
+            "operation": _operation(endpoint.method, endpoint.kind),
+            "model": endpoint.model,
+            "request_model": endpoint.request_model,
+            "response_is_list": endpoint.response_is_list,
+            "envelope_key": endpoint.envelope_key,
+            "status": endpoint.status,
+            "path_params": list(endpoint.path_params),
+            "example": endpoint.example,
+        }
+
+    def _crud_routes(self, collections: Dict[str, dict]) -> List[dict]:
+        """The five routes a table implies, for sources that describe no calls."""
+        routes: List[dict] = []
+        for model_name, meta in collections.items():
+            base = meta["path"]
+            pk = meta["pk"]
+            item = f"{base}/{{{pk}}}"
+            plural = base.strip("/") or model_name.lower()
+
+            def route(method, path, operation, status, summary, params=()):
+                return {
+                    "method": method,
+                    "path": path,
+                    "operation_id": f"{operation}_{plural}".replace("-", "_"),
+                    "summary": summary,
+                    "operation": operation,
+                    "model": model_name,
+                    "request_model": model_name if operation in ("create", "update") else None,
+                    "response_is_list": operation == "list",
+                    "envelope_key": None,
+                    "status": status,
+                    "path_params": list(params),
+                    "example": None,
+                }
+
+            routes.extend([
+                route("GET", base, "list", 200, f"List {plural}"),
+                route("POST", base, "create", 201, f"Create a {model_name}"),
+                route("GET", item, "retrieve", 200, f"Fetch one {model_name}", (pk,)),
+                route("PUT", item, "update", 200, f"Update a {model_name}", (pk,)),
+                route("DELETE", item, "delete", 204, f"Delete a {model_name}", (pk,)),
+            ])
+        return routes
+
+    # ── file writers ───────────────────────────────────────────────────────
+
+    def _write_models(self) -> None:
+        PydanticGenerator().generate(
+            (self.models, self.enums), self.output / "models.py"
+        )
+
+    def _generator_module(self) -> str:
+        return f"datagen_{self.name.replace('-', '_')}"
+
+    def _write_generator(self) -> None:
+        DatagenGenerator(
+            class_name=f"{_class_name(self.name)}Generator",
+            depot="depot/data.json",
+        ).generate(
+            (self.models, self.enums, self.datasets),
+            self.output / f"{self._generator_module()}.py",
+        )
+
+    def _write_depot(self, routes: List[dict], collections: Dict[str, dict]) -> None:
+        depot = self.output / "depot"
+
+        schema_path = depot / "schema.json"
+        JsonSchemaGenerator().generate((self.models, self.enums), schema_path)
+        schema = json.loads(schema_path.read_text())
+
+        spec = {
+            "name": self.name,
+            "title": self.title,
+            "kind": self.kind,
+            "source": self.source,
+            "summary": f"Generated by shuntgen from {self.source or self.kind}.",
+            "generator_module": self._generator_module(),
+            "collections": collections,
+            "routes": routes,
+            "models": schema.get("models", {}),
+        }
+        (depot / "spec.json").write_text(json.dumps(spec, indent=2) + "\n")
+
+        data = {d.model: d.rows for d in self.datasets if d.rows}
+        (depot / "data.json").write_text(json.dumps(data, indent=2) + "\n")
+
+        # Left empty on purpose: an override is a deliberate act, and a file
+        # pre-filled with guesses would quietly shadow the generated responses.
+        responses_path = depot / "responses.json"
+        if not responses_path.exists():
+            responses_path.write_text("{}\n")
+
+        config = {
+            "title": self.title,
+            "port": self.port,
+            "enable_random_delays": False,
+            "min_delay_ms": 200,
+            "max_delay_ms": 800,
+            "error_rate": 0.0,
+            # Imported rows are the real thing; only invent when there are none.
+            "prefill": 0 if any(d.rows for d in self.datasets) else 5,
+            "unknown_id": "generate",
+            "page_size": 50,
+        }
+        config_path = depot / "config.json"
+        if not config_path.exists():
+            config_path.write_text(json.dumps(config, indent=2) + "\n")
+
+    def _write_runtime(self) -> None:
+        shutil.copyfile(HERE / "runtime.py", self.output / "shunt_runtime.py")
+
+    def _write_app(self) -> None:
+        (self.output / "main.py").write_text(
+            f'''"""
+{self.title} shunt — GENERATED.
+
+The routes live in depot/spec.json and are built at import time by
+shunt_runtime. Edit the depot, not this file; regenerate with shuntgen.
+"""
+
+from pathlib import Path
+
+from shunt_runtime import build_app
+
+app = build_app(Path(__file__).parent)
+'''
+        )
+
+        (self.output / "run.py").write_text(
+            f'''"""Run the {self.title} shunt standalone."""
+
+import json
+import os
+from pathlib import Path
+
+import uvicorn
+
+BASE = Path(__file__).parent
+
+
+def port() -> int:
+    """PORT wins, then depot/config.json, then the generated default."""
+    if os.getenv("PORT"):
+        return int(os.environ["PORT"])
+    config = BASE / "depot" / "config.json"
+    if config.exists():
+        try:
+            return int(json.loads(config.read_text()).get("port", {self.port}))
+        except (OSError, ValueError):
+            pass
+    return {self.port}
+
+
+if __name__ == "__main__":
+    chosen = port()
+    print(f"{self.title} shunt on http://localhost:{{chosen}}  (UI at /, spec at /mock/spec)")
+    uvicorn.run("main:app", host="0.0.0.0", port=chosen, reload=False)
+'''
+        )
+
+    def _write_ui(self, routes: List[dict]) -> None:
+        template = (HERE / "templates" / "shunt_ui.html").read_text()
+        page = (
+            template.replace("%%THEME_CSS%%", _theme_css())
+            .replace("%%TITLE%%", self.title)
+            .replace("%%NAME%%", self.name)
+            .replace("%%SOURCE%%", self.source or self.kind)
+            .replace("%%ROUTE_COUNT%%", str(len(routes)))
+        )
+        (self.output / "templates" / "index.html").write_text(page)
+
+    def _write_cabinets(self) -> None:
+        if not self.cabinets:
+            return
+        (self.output / "cabinet.json").write_text(
+            json.dumps(
+                {
+                    "requires": self.cabinets,
+                    "note": (
+                        "Dependency containers this shunt expects. "
+                        "`python build.py --cfg <room>` composes them into the "
+                        "room's docker-compose.yml; on a cluster they install "
+                        "as rig addons of the same name."
+                    ),
+                },
+                indent=2,
+            )
+            + "\n"
+        )
+
+    def _write_readme(self, routes: List[dict], collections: Dict[str, dict]) -> None:
+        lines = [
+            f"# {self.title} shunt",
+            "",
+            f"Generated by shuntgen from `{self.source or self.kind}`.",
+            "",
+            "## Run",
+            "",
+            "```bash",
+            f"python run.py            # http://localhost:{self.port}",
+            f"PORT=9000 python run.py  # somewhere else",
+            "```",
+            "",
+            "## Routes",
+            "",
+            "| Method | Path | Does |",
+            "| --- | --- | --- |",
+        ]
+        for route in routes:
+            lines.append(
+                f"| {route['method']} | `{route['path']}` | {route['operation']} |"
+            )
+
+        lines += [
+            "",
+            "## Control",
+            "",
+            "| Endpoint | Purpose |",
+            "| --- | --- |",
+            "| `GET /health` | liveness |",
+            "| `GET /mock/spec` | the routes this shunt was built from |",
+            "| `GET /mock/stats` | call counts and row counts |",
+            "| `POST /mock/reset` | restore the imported rows, clear counters |",
+            "| `GET,POST /mock/config` | latency and error-injection knobs |",
+            "| `GET,POST /mock/responses` | pin an override; set a key to `null` to drop it |",
+            "",
+            "## Depot",
+            "",
+            "| File | Purpose |",
+            "| --- | --- |",
+            "| `spec.json` | routes, collections and schema — the source of truth |",
+            "| `responses.json` | pinned overrides, keyed `\"METHOD /path\"`; these win over everything |",
+            "| `data.json` | seed rows, keyed by model |",
+            "| `config.json` | delays, error rate, prefill, page size |",
+            "",
+        ]
+
+        if collections:
+            lines += ["## Collections", "", "| Model | Path | Key | Seed rows |", "| --- | --- | --- | --- |"]
+            for model, meta in collections.items():
+                lines.append(
+                    f"| {model} | `{meta['path']}` | `{meta['pk']}` | {meta['rows']} |"
+                )
+            lines.append("")
+
+        if self.cabinets:
+            lines += [
+                "## Dependencies",
+                "",
+                f"Declares the cabinets: {', '.join(f'`{c}`' for c in self.cabinets)}. "
+                "See `cabinet.json`.",
+                "",
+            ]
+
+        lines += [
+            "## Regenerating",
+            "",
+            "Everything here except `depot/responses.json` and `depot/config.json` is",
+            "overwritten on regeneration — those two are yours.",
+            "",
+        ]
+        (self.output / "README.md").write_text("\n".join(lines))
diff --git a/soleprint/station/tools/shuntgen/fixtures/petstore.yaml b/soleprint/station/tools/shuntgen/fixtures/petstore.yaml
new file mode 100644
index 0000000..bf8c9d5
--- /dev/null
+++ b/soleprint/station/tools/shuntgen/fixtures/petstore.yaml
@@ -0,0 +1,147 @@
+# A small OpenAPI 3 document used to exercise shuntgen and the OpenAPI loader.
+#
+# Deliberately covers the shapes that are easy to get wrong: an enum, a $ref to
+# another schema, an array of $ref, a wrapped collection, a path parameter, a
+# request body, and a response example.
+openapi: 3.0.3
+info:
+  title: Petstore
+  version: 1.0.0
+
+paths:
+  /pets:
+    get:
+      operationId: listPets
+      summary: List all pets
+      responses:
+        "200":
+          description: A page of pets
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/PetPage"
+    post:
+      operationId: createPet
+      summary: Create a pet
+      requestBody:
+        required: true
+        content:
+          application/json:
+            schema:
+              $ref: "#/components/schemas/Pet"
+      responses:
+        "201":
+          description: The created pet
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/Pet"
+
+  /pets/{petId}:
+    get:
+      operationId: getPet
+      summary: Fetch one pet
+      parameters:
+        - name: petId
+          in: path
+          required: true
+          schema:
+            type: integer
+      responses:
+        "200":
+          description: The pet
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/Pet"
+              example:
+                id: 7
+                name: "Rocinante"
+                status: "available"
+        "404":
+          description: No such pet
+    delete:
+      operationId: deletePet
+      summary: Remove a pet
+      parameters:
+        - name: petId
+          in: path
+          required: true
+          schema:
+            type: integer
+      responses:
+        "204":
+          description: Deleted
+
+  /categories:
+    get:
+      operationId: listCategories
+      summary: List categories
+      responses:
+        "200":
+          description: Every category
+          content:
+            application/json:
+              schema:
+                type: array
+                items:
+                  $ref: "#/components/schemas/Category"
+
+components:
+  schemas:
+    Pet:
+      type: object
+      description: An animal available for adoption.
+      required: [id, name]
+      properties:
+        id:
+          type: integer
+          format: int64
+        name:
+          type: string
+        status:
+          type: string
+          enum: [available, pending, sold]
+        weight_kg:
+          type: number
+        neutered:
+          type: boolean
+        born_on:
+          type: string
+          format: date
+        category:
+          $ref: "#/components/schemas/Category"
+        tags:
+          type: array
+          items:
+            $ref: "#/components/schemas/Tag"
+
+    Category:
+      type: object
+      description: A grouping of pets.
+      required: [id, name]
+      properties:
+        id:
+          type: integer
+        name:
+          type: string
+
+    Tag:
+      type: object
+      required: [id]
+      properties:
+        id:
+          type: string
+          format: uuid
+        label:
+          type: string
+
+    PetPage:
+      type: object
+      properties:
+        items:
+          type: array
+          items:
+            $ref: "#/components/schemas/Pet"
+        total:
+          type: integer
diff --git a/soleprint/station/tools/shuntgen/fixtures/sheets/customers.csv b/soleprint/station/tools/shuntgen/fixtures/sheets/customers.csv
new file mode 100644
index 0000000..6d6241e
--- /dev/null
+++ b/soleprint/station/tools/shuntgen/fixtures/sheets/customers.csv
@@ -0,0 +1,6 @@
+id,name,email,city,active,signed_up_at,credit_limit
+1,Ada Alvarez,ada@example.com,Buenos Aires,true,2024-03-11,15000.50
+2,Bruno Bianchi,bruno@example.com,Rosario,true,2024-05-02,8000
+3,Camila Castro,camila@example.com,Cordoba,false,2023-11-27,
+4,Diego Duarte,diego@example.com,Montevideo,true,2025-01-19,22500.75
+5,Elena Esposito,elena@example.com,Santiago,false,2025-06-30,3000
diff --git a/soleprint/station/tools/shuntgen/fixtures/sheets/invoices.csv b/soleprint/station/tools/shuntgen/fixtures/sheets/invoices.csv
new file mode 100644
index 0000000..e4f970d
--- /dev/null
+++ b/soleprint/station/tools/shuntgen/fixtures/sheets/invoices.csv
@@ -0,0 +1,7 @@
+invoice_id,customer_id,issued_on,total,currency,paid
+1001,1,2025-02-03,4200.00,ARS,true
+1002,1,2025-03-03,3150.25,ARS,false
+1003,2,2025-03-14,900.00,USD,true
+1004,4,2025-04-21,12800.40,ARS,false
+1005,5,2025-05-05,150.00,USD,true
+1006,2,2025-06-11,7300.10,ARS,true
diff --git a/soleprint/station/tools/shuntgen/fixtures/sheets/line_items.ods b/soleprint/station/tools/shuntgen/fixtures/sheets/line_items.ods
new file mode 100644
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diff --git a/soleprint/station/tools/shuntgen/runtime.py b/soleprint/station/tools/shuntgen/runtime.py
new file mode 100644
index 0000000..076cfe7
--- /dev/null
+++ b/soleprint/station/tools/shuntgen/runtime.py
@@ -0,0 +1,489 @@
+"""
+Shunt runtime — copied verbatim into every generated shunt as shunt_runtime.py.
+
+A generated shunt is a spec plus this file. The routes are built at startup
+from depot/spec.json rather than written out as source, which is what keeps the
+generated code short enough to read and the behaviour in one reviewable place:
+fixing a bug here fixes it in every shunt, and regenerating is a copy.
+
+It imports nothing from soleprint. A shunt runs as its own process on its own
+port — often in a test harness that has no soleprint on the path — so the only
+dependencies are fastapi and the standard library.
+
+Where a response comes from, first hit wins:
+
+  1. depot/responses.json   a pinned override, the documented "METHOD /path" map
+  2. the store              rows imported from spreadsheets, plus anything POSTed
+  3. the spec example       an `example` carried over from the source document
+  4. the generator          datagen_<name>.py, synthesising from the schema
+  5. {}                     nothing else was available
+
+The store is what makes it behave like a service rather than a random-value
+faucet: POST something and GET it back, ask for /pets/7 and get the pet whose
+id is 7.
+"""
+
+import importlib.util
+import json
+import random
+import re
+import time
+import uuid
+from pathlib import Path
+from typing import Any, Dict, List, Optional
+
+from fastapi import FastAPI, HTTPException, Request
+from fastapi.responses import HTMLResponse, JSONResponse, Response
+
+DEFAULT_CONFIG: Dict[str, Any] = {
+    "title": "Shunt",
+    "port": 8099,
+    # Latency and failure injection, the knobs the mercadopago shunt proved out.
+    "enable_random_delays": False,
+    "min_delay_ms": 200,
+    "max_delay_ms": 800,
+    "error_rate": 0.0,
+    # Rows to synthesise per collection that arrived with none, so a GET
+    # answers with something on the first call rather than an empty list.
+    "prefill": 5,
+    # "generate" invents a record for an unknown id; "404" refuses it. Generate
+    # by default: a client pointed at a fresh shunt should just work, and a
+    # test that needs the error path can pin it or flip this.
+    "unknown_id": "generate",
+    "page_size": 50,
+}
+
+
+class Shunt:
+    """Holds a shunt's spec, config, store and counters."""
+
+    def __init__(self, base: Path):
+        self.base = Path(base)
+        self.depot = self.base / "depot"
+        self.spec: Dict[str, Any] = self._read_json("spec.json", {})
+        self.responses: Dict[str, Any] = self._read_json("responses.json", {})
+        self.config: Dict[str, Any] = {
+            **DEFAULT_CONFIG,
+            **self._read_json("config.json", {}),
+        }
+        self.seed: Dict[str, List[dict]] = self._read_json("data.json", {})
+        self.collections: Dict[str, dict] = self.spec.get("collections", {}) or {}
+        self.stats: Dict[str, int] = {}
+        self.generator = self._load_generator()
+        self.store: Dict[str, List[dict]] = {}
+        self.reset()
+
+    # ── loading ────────────────────────────────────────────────────────────
+
+    def _read_json(self, name: str, fallback: Any) -> Any:
+        path = self.depot / name
+        if not path.exists():
+            return fallback
+        try:
+            return json.loads(path.read_text())
+        except (OSError, ValueError):
+            # A hand-edited responses.json with a stray comma should degrade to
+            # "no overrides", not stop the shunt from booting.
+            return fallback
+
+    def _load_generator(self):
+        """Import the sibling datagen module, if one was generated."""
+        module_name = self.spec.get("generator_module")
+        if not module_name:
+            return None
+        path = self.base / f"{module_name}.py"
+        if not path.exists():
+            return None
+        try:
+            spec = importlib.util.spec_from_file_location(module_name, path)
+            if not spec or not spec.loader:
+                return None
+            module = importlib.util.module_from_spec(spec)
+            spec.loader.exec_module(module)
+        except Exception:
+            return None
+
+        # Same discovery rule as station/tools/datagen/api.py: the class whose
+        # name ends in Generator and is not the base.
+        for name, obj in vars(module).items():
+            if (
+                isinstance(obj, type)
+                and name.endswith("Generator")
+                and name != "BaseDataGenerator"
+            ):
+                try:
+                    return obj()
+                except Exception:
+                    return None
+        return None
+
+    def reset(self) -> None:
+        """Restore the store to its imported state and clear the counters."""
+        self.store = {model: [dict(r) for r in rows] for model, rows in self.seed.items()}
+        self.stats = {}
+
+        prefill = int(self.config.get("prefill") or 0)
+        if not prefill or not self.generator:
+            return
+        for model in self.collections:
+            if self.store.get(model):
+                continue
+            self.store[model] = self.synthesise(model, prefill, sequential_keys=True)
+
+    # ── generation ─────────────────────────────────────────────────────────
+
+    def synthesise(
+        self, model: str, count: int = 1, sequential_keys: bool = False
+    ) -> List[dict]:
+        """Build records for a model, or [] if nothing can."""
+        if not self.generator:
+            return []
+        try:
+            rows = self.generator.generate(model, count)
+        except Exception:
+            return []
+
+        if sequential_keys:
+            # Prefilled rows are the ones a caller will look up by id, so their
+            # keys have to be predictable — 1..n, not whatever random produced.
+            pk = (self.collections.get(model) or {}).get("pk")
+            pk_type = (self.collections.get(model) or {}).get("pk_type")
+            if pk and pk_type in ("int", "bigint"):
+                for index, row in enumerate(rows, start=1):
+                    row[pk] = index
+        return rows
+
+    # ── store operations ───────────────────────────────────────────────────
+
+    def rows(self, model: str) -> List[dict]:
+        return self.store.setdefault(model, [])
+
+    def coerce_key(self, model: str, raw: Any) -> Any:
+        """Match a path segment against the key type the rows actually use."""
+        pk_type = (self.collections.get(model) or {}).get("pk_type")
+        if pk_type in ("int", "bigint"):
+            try:
+                return int(raw)
+            except (TypeError, ValueError):
+                return raw
+        return str(raw)
+
+    def find(self, model: str, key: Any) -> Optional[dict]:
+        pk = (self.collections.get(model) or {}).get("pk")
+        if not pk:
+            return None
+        wanted = self.coerce_key(model, key)
+        for row in self.rows(model):
+            if row.get(pk) == wanted or str(row.get(pk)) == str(wanted):
+                return row
+        return None
+
+    def next_key(self, model: str) -> Any:
+        pk_meta = self.collections.get(model) or {}
+        pk, pk_type = pk_meta.get("pk"), pk_meta.get("pk_type")
+        if not pk:
+            return None
+        if pk_type in ("int", "bigint"):
+            keys = [r.get(pk) for r in self.rows(model) if isinstance(r.get(pk), int)]
+            return (max(keys) + 1) if keys else 1
+        return str(uuid.uuid4())
+
+    # ── request shaping ────────────────────────────────────────────────────
+
+    def maybe_fail(self) -> None:
+        rate = float(self.config.get("error_rate") or 0)
+        if rate > 0 and random.random() < rate:
+            raise HTTPException(
+                status_code=500,
+                detail="injected failure (error_rate is above zero)",
+            )
+
+    def maybe_delay(self) -> None:
+        if not self.config.get("enable_random_delays"):
+            return
+        low = int(self.config.get("min_delay_ms") or 0)
+        high = max(low, int(self.config.get("max_delay_ms") or 0))
+        time.sleep(random.randint(low, high) / 1000.0)
+
+    def pinned(self, method: str, template: str, actual: str) -> Any:
+        """A configured override, matched on the template or the concrete path."""
+        for key in (f"{method} {template}", f"{method} {actual}"):
+            if key in self.responses:
+                return self.responses[key]
+        return None
+
+    def count(self, key: str) -> None:
+        self.stats[key] = self.stats.get(key, 0) + 1
+
+
+# ── route handlers ─────────────────────────────────────────────────────────
+
+
+def _filtered(rows: List[dict], params) -> List[dict]:
+    """Narrow a collection by any query parameter naming a field."""
+    reserved = {"limit", "offset", "page", "page_size"}
+    out = rows
+    for name, value in params.multi_items():
+        if name in reserved:
+            continue
+        if not out or name not in out[0]:
+            continue
+        out = [r for r in out if str(r.get(name)) == str(value)]
+    return out
+
+
+def _paged(rows: List[dict], params, default_size: int):
+    try:
+        limit = int(params.get("limit", params.get("page_size", default_size)))
+    except (TypeError, ValueError):
+        limit = default_size
+    try:
+        offset = int(params.get("offset", 0))
+    except (TypeError, ValueError):
+        offset = 0
+    limit = max(0, min(limit, 1000))
+    return rows[offset : offset + limit]
+
+
+def _make_handler(shunt: Shunt, route: dict):
+    """Build the endpoint function for one route in the spec."""
+    method = route["method"]
+    template = route["path"]
+    model = route.get("model")
+    operation = route.get("operation", "action")
+    envelope = route.get("envelope_key")
+    status = int(route.get("status") or 200)
+    example = route.get("example")
+    key_param = route["path_params"][-1] if route.get("path_params") else None
+    route_key = f"{method} {template}"
+
+    async def handler(request: Request):
+        shunt.count(route_key)
+        shunt.maybe_fail()
+        shunt.maybe_delay()
+
+        override = shunt.pinned(method, template, request.url.path)
+        if override is not None:
+            return JSONResponse(override, status_code=status)
+
+        body: Any = None
+        if method in ("POST", "PUT", "PATCH"):
+            try:
+                body = await request.json()
+            except Exception:
+                body = None
+
+        known = model in shunt.collections
+        key = request.path_params.get(key_param) if key_param else None
+
+        if known and operation == "list":
+            rows = _filtered(shunt.rows(model), request.query_params)
+            page = _paged(rows, request.query_params, int(shunt.config["page_size"]))
+            if envelope:
+                return JSONResponse({envelope: page, "total": len(rows)}, status_code=status)
+            return JSONResponse(page, status_code=status)
+
+        if known and operation == "retrieve":
+            found = shunt.find(model, key)
+            if found is not None:
+                return JSONResponse(found, status_code=status)
+            if shunt.config.get("unknown_id") == "404":
+                raise HTTPException(status_code=404, detail=f"No {model} with id {key}")
+            # Nothing stored under that id, so answer with the closest thing to
+            # an authored response: the spec's own example if there is one,
+            # otherwise a synthesised record. Either way it wears the id that
+            # was asked for — a record whose id disagrees with its own URL
+            # breaks clients that re-read what they just fetched.
+            pk = (shunt.collections.get(model) or {}).get("pk")
+            if isinstance(example, dict):
+                stand_in = dict(example)
+            else:
+                made = shunt.synthesise(model, 1)
+                stand_in = made[0] if made else None
+            if stand_in is not None:
+                if pk:
+                    stand_in[pk] = shunt.coerce_key(model, key)
+                return JSONResponse(stand_in, status_code=status)
+
+        if known and operation == "create":
+            sent = dict(body) if isinstance(body, dict) else {}
+            pk = (shunt.collections.get(model) or {}).get("pk")
+            # Fill the gaps from the schema so a partial POST still comes back
+            # as a complete record.
+            made = shunt.synthesise(model, 1)
+            record = {**(made[0] if made else {}), **sent}
+            # The gap-filler samples an existing row when there are rows to
+            # sample, so it supplies that row's key too. Only a key the caller
+            # actually sent may survive; anything else gets a fresh one, or a
+            # POST silently overwrites an existing record's identity.
+            if pk and not sent.get(pk):
+                record[pk] = shunt.next_key(model)
+            shunt.rows(model).append(record)
+            return JSONResponse(record, status_code=status if status >= 200 else 201)
+
+        if known and operation == "update":
+            found = shunt.find(model, key)
+            if found is None:
+                if shunt.config.get("unknown_id") == "404":
+                    raise HTTPException(
+                        status_code=404, detail=f"No {model} with id {key}"
+                    )
+                found = {}
+                pk = (shunt.collections.get(model) or {}).get("pk")
+                if pk:
+                    found[pk] = shunt.coerce_key(model, key)
+                shunt.rows(model).append(found)
+            if isinstance(body, dict):
+                found.update(body)
+            return JSONResponse(found, status_code=status)
+
+        if known and operation == "delete":
+            found = shunt.find(model, key)
+            if found is not None:
+                shunt.rows(model).remove(found)
+            elif shunt.config.get("unknown_id") == "404":
+                raise HTTPException(status_code=404, detail=f"No {model} with id {key}")
+            return Response(status_code=204)
+
+        if example is not None:
+            return JSONResponse(example, status_code=status)
+
+        if model:
+            made = shunt.synthesise(model, 1)
+            if made:
+                payload: Any = made[0]
+                if route.get("response_is_list"):
+                    rows = shunt.synthesise(model, 3) or made
+                    payload = {envelope: rows, "total": len(rows)} if envelope else rows
+                return JSONResponse(payload, status_code=status)
+
+        if status == 204:
+            return Response(status_code=204)
+        return JSONResponse({}, status_code=status)
+
+    handler.__name__ = route.get("operation_id") or re.sub(
+        r"\W+", "_", f"{method}_{template}"
+    ).strip("_")
+    return handler
+
+
+def _sanitise(path: str) -> str:
+    """Make spec path parameters legal Starlette converters."""
+
+    def fix(match):
+        name = re.sub(r"\W+", "_", match.group(1)).strip("_") or "param"
+        if name[0].isdigit():
+            name = f"p_{name}"
+        return "{" + name + "}"
+
+    return re.sub(r"\{([^}]*)\}", fix, path)
+
+
+def build_app(base: Path) -> FastAPI:
+    """Assemble a shunt's FastAPI app from the spec in its depot."""
+    base = Path(base)
+    shunt = Shunt(base)
+    title = shunt.spec.get("title") or shunt.config.get("title") or "Shunt"
+
+    app = FastAPI(title=title, description=shunt.spec.get("summary", ""))
+
+    @app.get("/health")
+    def health():
+        return {
+            "status": "ok",
+            "shunt": shunt.spec.get("name", "shunt"),
+            "routes": len(shunt.spec.get("routes", [])),
+        }
+
+    @app.get("/mock/spec")
+    def mock_spec():
+        return shunt.spec
+
+    @app.get("/mock/stats")
+    def mock_stats():
+        return {
+            "calls": shunt.stats,
+            "total": sum(shunt.stats.values()),
+            "rows": {model: len(rows) for model, rows in shunt.store.items()},
+        }
+
+    @app.post("/mock/reset")
+    @app.get("/mock/reset")
+    def mock_reset():
+        shunt.reset()
+        return {"status": "reset", "rows": {m: len(r) for m, r in shunt.store.items()}}
+
+    @app.get("/mock/config")
+    def mock_config_get():
+        return shunt.config
+
+    @app.post("/mock/config")
+    async def mock_config_set(request: Request):
+        try:
+            incoming = await request.json()
+        except Exception:
+            raise HTTPException(status_code=400, detail="Body must be a JSON object")
+        if not isinstance(incoming, dict):
+            raise HTTPException(status_code=400, detail="Body must be a JSON object")
+        # Only known knobs, so a typo is reported rather than silently stored.
+        unknown = set(incoming) - set(DEFAULT_CONFIG)
+        if unknown:
+            raise HTTPException(
+                status_code=400, detail=f"Unknown settings: {sorted(unknown)}"
+            )
+        shunt.config.update(incoming)
+        return shunt.config
+
+    @app.get("/mock/responses")
+    def mock_responses():
+        return shunt.responses
+
+    @app.post("/mock/responses")
+    async def mock_responses_set(request: Request):
+        """Pin or clear an override without restarting — set a key to null to drop it."""
+        try:
+            incoming = await request.json()
+        except Exception:
+            raise HTTPException(status_code=400, detail="Body must be a JSON object")
+        if not isinstance(incoming, dict):
+            raise HTTPException(status_code=400, detail="Body must be a JSON object")
+        for key, value in incoming.items():
+            if value is None:
+                shunt.responses.pop(key, None)
+            else:
+                shunt.responses[key] = value
+        return shunt.responses
+
+    # Static segments before parameterised ones, so /pets/search is not
+    # swallowed by /pets/{petId} when a spec declares both.
+    routes = sorted(
+        shunt.spec.get("routes", []),
+        key=lambda r: (len(r.get("path_params") or []), r.get("path", "")),
+    )
+
+    claimed = set()
+    for route in routes:
+        path = _sanitise(route["path"])
+        key = (route["method"], path)
+        if key in claimed:
+            continue
+        claimed.add(key)
+        app.add_api_route(
+            path,
+            _make_handler(shunt, route),
+            methods=[route["method"]],
+            name=route.get("operation_id") or None,
+            summary=route.get("summary") or None,
+        )
+
+    if ("GET", "/") not in claimed:
+
+        @app.get("/", response_class=HTMLResponse)
+        def config_ui():
+            page = base / "templates" / "index.html"
+            if page.exists():
+                return HTMLResponse(page.read_text())
+            return HTMLResponse(f"<h1>{title}</h1><p>See /mock/spec and /health.</p>")
+
+    app.state.shunt = shunt
+    return app
diff --git a/soleprint/station/tools/shuntgen/templates/index.html b/soleprint/station/tools/shuntgen/templates/index.html
new file mode 100644
index 0000000..48deed4
--- /dev/null
+++ b/soleprint/station/tools/shuntgen/templates/index.html
@@ -0,0 +1,294 @@
+<!DOCTYPE html>
+<html lang="en" data-theme="soleprint">
+<head>
+    <meta charset="utf-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1">
+    <title>shuntgen</title>
+    <link rel="stylesheet" href="/theme.css">
+    <style>
+    * { box-sizing: border-box; }
+    body { margin: 0; padding: var(--space-6); max-width: 1200px; }
+
+    header { display: flex; align-items: baseline; gap: var(--space-3); flex-wrap: wrap;
+             padding-bottom: var(--space-4); border-bottom: var(--hairline) solid var(--border); }
+    h1 { margin: 0; font-size: 20px; color: var(--accent-text); }
+    .sub { color: var(--muted); font-family: var(--font-mono); font-size: 12px; }
+
+    h2 { font-size: 13px; color: var(--muted); margin: var(--space-6) 0 var(--space-3); }
+
+    .cols { display: grid; grid-template-columns: 340px 1fr; gap: var(--space-4);
+            align-items: start; margin-top: var(--space-4); }
+    @media (max-width: 860px) { .cols { grid-template-columns: 1fr; } }
+
+    .panel { background: var(--surface); border: var(--hairline) solid var(--border);
+             border-radius: var(--radius-lg); padding: var(--space-4); }
+
+    label { display: block; font-size: 11px; color: var(--muted); margin-top: var(--space-3);
+            text-transform: uppercase; letter-spacing: var(--label-spacing); }
+    input, select { width: 100%; padding: 6px 8px; margin-top: 4px;
+                    font-family: var(--font-mono); font-size: 12px; }
+    input[type="file"] { padding: 4px; font-family: var(--font-ui); }
+    .row { display: flex; gap: var(--space-2); }
+    .row > * { flex: 1; }
+    .actions { display: flex; gap: var(--space-2); margin-top: var(--space-4); }
+    button { padding: 7px 14px; font-size: 12px; }
+    button.primary { background: var(--accent); color: var(--bg); border-color: var(--accent); }
+    button.primary:hover:not(:disabled) { background: var(--accent-dim); color: var(--bg); }
+
+    table { width: 100%; border-collapse: collapse; font-size: 12px; }
+    th { text-align: left; padding: 6px 8px; color: var(--muted); font-weight: 600;
+         font-size: 10px; text-transform: uppercase; letter-spacing: var(--label-spacing);
+         border-bottom: var(--hairline) solid var(--border); }
+    td { padding: 6px 8px; border-bottom: var(--hairline) solid var(--border);
+         font-family: var(--font-mono); }
+    tr:hover td { background: var(--bg-2); }
+
+    .verb { font-weight: 600; font-size: 10px; padding: 1px 6px; border-radius: var(--radius-sm);
+            border: 1px solid currentColor; }
+    .GET { color: var(--status-info); }
+    .POST { color: var(--status-ok); }
+    .PUT, .PATCH { color: var(--status-warn); }
+    .DELETE { color: var(--status-error); }
+
+    .msg { margin-top: var(--space-3); padding: var(--space-3); border-radius: var(--radius);
+           font-size: 12px; border: var(--hairline) solid var(--border); display: none; }
+    .msg.show { display: block; }
+    .msg.ok { border-color: var(--status-ok); color: var(--status-ok); }
+    .msg.bad { border-color: var(--status-error); color: var(--status-error); }
+    .msg code { color: var(--text); }
+
+    .empty { color: var(--dim); font-size: 12px; padding: var(--space-3); }
+    .note { color: var(--dim); font-size: 11px; margin-top: var(--space-2); }
+    .chip { display: inline-block; font-family: var(--font-mono); font-size: 10px;
+            padding: 1px 6px; border-radius: var(--radius-sm);
+            border: var(--hairline) solid var(--border); color: var(--muted); }
+    </style>
+</head>
+<body>
+    <header>
+        <h1>shuntgen</h1>
+        <span class="sub">a spec or a folder of sheets &rarr; a running fake service</span>
+    </header>
+
+    <div class="cols">
+        <div>
+            <h2>Source</h2>
+            <div class="panel">
+                <label for="source">Spec or sheet folder</label>
+                <select id="source"><option value="">loading…</option></select>
+
+                <label for="upload">…or upload</label>
+                <input type="file" id="upload"
+                       accept=".json,.yaml,.yml,.csv,.tsv,.ods">
+                <p class="note">
+                    A spec (.json/.yaml) becomes routes. Sheets (.csv/.tsv/.ods) become
+                    models with CRUD over their real rows — upload them into a folder
+                    to import several at once.
+                </p>
+                <label for="folder">Upload into folder (sheets)</label>
+                <input type="text" id="folder" placeholder="e.g. invoicing">
+
+                <h2>Shunt</h2>
+                <label for="name">Name</label>
+                <input type="text" id="name" placeholder="petstore">
+
+                <div class="row">
+                    <div>
+                        <label for="port">Port</label>
+                        <input type="number" id="port" value="8099">
+                    </div>
+                    <div>
+                        <label for="kind">Kind</label>
+                        <select id="kind">
+                            <option value="auto">auto</option>
+                            <option value="openapi">openapi</option>
+                            <option value="tabular">tabular</option>
+                        </select>
+                    </div>
+                </div>
+
+                <label for="cabinets">Cabinets (comma-separated)</label>
+                <input type="text" id="cabinets" placeholder="postgres,redis">
+
+                <div class="actions">
+                    <button type="button" id="preview">Preview</button>
+                    <button type="button" id="generate" class="primary">Generate</button>
+                </div>
+
+                <div class="msg" id="msg"></div>
+            </div>
+        </div>
+
+        <div>
+            <h2>What it will serve</h2>
+            <div class="panel">
+                <table id="routes">
+                    <thead>
+                        <tr><th>Method</th><th>Path</th><th>Does</th><th>Model</th></tr>
+                    </thead>
+                    <tbody><tr><td colspan="4" class="empty">pick a source and preview</td></tr></tbody>
+                </table>
+            </div>
+
+            <h2>Existing shunts</h2>
+            <div class="panel">
+                <table id="shunts">
+                    <thead>
+                        <tr><th>Name</th><th>Kind</th><th>Source</th><th>Routes</th><th>Models</th></tr>
+                    </thead>
+                    <tbody><tr><td colspan="5" class="empty">loading…</td></tr></tbody>
+                </table>
+            </div>
+        </div>
+    </div>
+
+    <script src="/theme.js" defer></script>
+    <script>
+    const BASE = "/station/tools/shuntgen";
+    const $ = (id) => document.getElementById(id);
+
+    function say(text, ok) {
+        const box = $("msg");
+        box.className = "msg show " + (ok ? "ok" : "bad");
+        box.innerHTML = text;
+    }
+
+    function body() {
+        return {
+            name: $("name").value.trim() || "preview",
+            source: $("source").value,
+            kind: $("kind").value,
+            port: Number($("port").value) || 8099,
+            cabinets: $("cabinets").value.split(",").map(s => s.trim()).filter(Boolean),
+        };
+    }
+
+    async function post(path, payload) {
+        const response = await fetch(BASE + path, {
+            method: "POST",
+            headers: { "content-type": "application/json" },
+            body: JSON.stringify(payload),
+        });
+        const data = await response.json().catch(() => ({}));
+        if (!response.ok) throw new Error(data.detail || response.statusText);
+        return data;
+    }
+
+    function cell(text) {
+        const td = document.createElement("td");
+        td.textContent = text == null ? "" : String(text);
+        return td;
+    }
+
+    function fill(table, rows, columns, emptyText) {
+        const tbody = table.querySelector("tbody");
+        tbody.replaceChildren();
+        if (!rows.length) {
+            const tr = document.createElement("tr");
+            const td = cell(emptyText);
+            td.colSpan = columns;
+            td.className = "empty";
+            tr.appendChild(td);
+            tbody.appendChild(tr);
+        }
+        return tbody;
+    }
+
+    async function loadSources() {
+        const data = await (await fetch(BASE + "/api/sources")).json();
+        const select = $("source");
+        select.replaceChildren();
+        const all = [...data.specs.map(p => ["spec", p]), ...data.sheets.map(p => ["sheets", p])];
+        if (!all.length) {
+            select.appendChild(new Option("nothing uploaded yet", ""));
+            return;
+        }
+        for (const [kind, path] of all) {
+            select.appendChild(new Option(`${kind}  ·  ${path}`, path));
+        }
+        if (!$("name").value) {
+            const guess = all[0][1].split("/").pop().replace(/\.[^.]+$/, "");
+            $("name").placeholder = guess;
+        }
+    }
+
+    async function loadShunts() {
+        const data = await (await fetch(BASE + "/api/shunts")).json();
+        const tbody = fill($("shunts"), data.shunts, 5, "no shunts yet");
+        for (const shunt of data.shunts) {
+            const tr = document.createElement("tr");
+            tr.appendChild(cell(shunt.name));
+            tr.appendChild(cell(shunt.generated ? shunt.kind : "hand-written"));
+            tr.appendChild(cell(shunt.source));
+            tr.appendChild(cell(shunt.routes));
+            tr.appendChild(cell(shunt.models));
+            tbody.appendChild(tr);
+        }
+    }
+
+    function showRoutes(routes) {
+        const tbody = fill($("routes"), routes, 4, "nothing to serve");
+        for (const route of routes) {
+            const tr = document.createElement("tr");
+            const verb = document.createElement("td");
+            const badge = document.createElement("span");
+            badge.className = "verb " + route.method;
+            badge.textContent = route.method;
+            verb.appendChild(badge);
+            tr.appendChild(verb);
+            tr.appendChild(cell(route.path));
+            tr.appendChild(cell(route.operation));
+            tr.appendChild(cell(route.model));
+            tbody.appendChild(tr);
+        }
+    }
+
+    $("upload").addEventListener("change", async (event) => {
+        const file = event.target.files[0];
+        if (!file) return;
+        const form = new FormData();
+        form.append("file", file);
+        const folder = $("folder").value.trim();
+        const url = BASE + "/api/upload" + (folder ? "?folder=" + encodeURIComponent(folder) : "");
+        const response = await fetch(url, { method: "POST", body: form });
+        const data = await response.json().catch(() => ({}));
+        if (!response.ok) {
+            say(data.detail || "Upload failed", false);
+            return;
+        }
+        say("Uploaded <code>" + data.path + "</code>", true);
+        await loadSources();
+        $("source").value = folder
+            ? data.path.split("/").slice(0, -1).join("/")
+            : data.path;
+    });
+
+    $("preview").addEventListener("click", async () => {
+        if (!$("source").value) { say("Pick or upload a source first", false); return; }
+        try {
+            const data = await post("/api/preview", body());
+            showRoutes(data.routes);
+            say(
+                `${data.models.length} models, ${data.routes.length} routes` +
+                (data.rows ? `, ${data.rows} rows` : "") + ` (${data.kind})`, true
+            );
+        } catch (error) { say(error.message, false); }
+    });
+
+    $("generate").addEventListener("click", async () => {
+        if (!$("source").value) { say("Pick or upload a source first", false); return; }
+        if (!$("name").value.trim()) { say("Give the shunt a name", false); return; }
+        try {
+            const data = await post("/api/generate", body());
+            say(
+                `Wrote <code>${data.path}</code> — ${data.routes} routes. ` +
+                `Run it with <code>${data.run}</code>`, true
+            );
+            await loadShunts();
+        } catch (error) { say(error.message, false); }
+    });
+
+    Promise.all([loadSources(), loadShunts()]).catch((e) => say(e.message, false));
+    </script>
+</body>
+</html>
diff --git a/soleprint/station/tools/shuntgen/templates/shunt_ui.html b/soleprint/station/tools/shuntgen/templates/shunt_ui.html
new file mode 100644
index 0000000..e83f634
--- /dev/null
+++ b/soleprint/station/tools/shuntgen/templates/shunt_ui.html
@@ -0,0 +1,242 @@
+<!DOCTYPE html>
+<!--
+  Config UI for a generated shunt. Emitted into <shunt>/templates/index.html
+  with the theme inlined, because a shunt serves this on its own port and
+  cannot reach soleprint's /theme.css.
+
+  Placeholders are filled by emit.py: %%THEME_CSS%%, %%TITLE%%, %%NAME%%,
+  %%SOURCE%%, %%ROUTE_COUNT%%.
+-->
+<html lang="en" data-theme="soleprint">
+<head>
+    <meta charset="utf-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1">
+    <title>%%TITLE%% shunt</title>
+    <style>
+%%THEME_CSS%%
+
+    * { box-sizing: border-box; }
+    body { margin: 0; padding: var(--space-6); max-width: 1100px; }
+
+    header { display: flex; align-items: baseline; gap: var(--space-3); flex-wrap: wrap;
+             padding-bottom: var(--space-4); border-bottom: var(--hairline) solid var(--border); }
+    h1 { margin: 0; font-size: 20px; color: var(--accent-text); }
+    .sub { color: var(--muted); font-family: var(--font-mono); font-size: 12px; }
+    .dot { width: 8px; height: 8px; border-radius: 50%; background: var(--status-ok);
+           display: inline-block; margin-right: 6px; }
+
+    h2 { font-size: 13px; color: var(--muted); margin: var(--space-6) 0 var(--space-3); }
+
+    .panel { background: var(--surface); border: var(--hairline) solid var(--border);
+             border-radius: var(--radius-lg); padding: var(--space-4); }
+    .grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
+            gap: var(--space-3); }
+
+    table { width: 100%; border-collapse: collapse; font-size: 12px; }
+    th { text-align: left; padding: 6px 8px; color: var(--muted); font-weight: 600;
+         font-size: 10px; text-transform: uppercase; letter-spacing: var(--label-spacing);
+         border-bottom: var(--hairline) solid var(--border); }
+    td { padding: 6px 8px; border-bottom: var(--hairline) solid var(--border);
+         font-family: var(--font-mono); }
+    tr:hover td { background: var(--bg-2); }
+
+    .verb { font-weight: 600; font-size: 10px; padding: 1px 6px; border-radius: var(--radius-sm);
+            border: 1px solid currentColor; }
+    .GET { color: var(--status-info); }
+    .POST { color: var(--status-ok); }
+    .PUT, .PATCH { color: var(--status-warn); }
+    .DELETE { color: var(--status-error); }
+
+    a.route { color: var(--text); text-decoration: none; border-bottom: 1px solid transparent; }
+    a.route:hover { color: var(--accent-text); border-bottom-color: var(--accent); }
+
+    label { display: flex; align-items: center; justify-content: space-between;
+            gap: var(--space-2); font-size: 12px; color: var(--muted); padding: 4px 0; }
+    input[type="number"], input[type="text"], select { padding: 4px 8px; width: 130px;
+                                                       font-family: var(--font-mono); font-size: 12px; }
+    input[type="checkbox"] { width: auto; }
+    .actions { display: flex; gap: var(--space-2); margin-top: var(--space-3); }
+    button { padding: 6px 12px; font-size: 12px; }
+
+    pre { background: var(--bg); border: var(--hairline) solid var(--border);
+          border-radius: var(--radius); padding: var(--space-3); overflow-x: auto;
+          font-size: 11px; margin: 0; max-height: 320px; }
+    .note { color: var(--dim); font-size: 11px; margin-top: var(--space-2); }
+    .empty { color: var(--dim); font-size: 12px; }
+    </style>
+</head>
+<body>
+    <header>
+        <h1>%%TITLE%%</h1>
+        <span class="sub"><span class="dot"></span>shunt &middot; %%NAME%%</span>
+        <span class="sub">%%ROUTE_COUNT%% routes from %%SOURCE%%</span>
+    </header>
+
+    <h2>Routes</h2>
+    <div class="panel">
+        <table id="routes">
+            <thead>
+                <tr><th>Method</th><th>Path</th><th>Does</th><th>Model</th><th>Calls</th></tr>
+            </thead>
+            <tbody><tr><td colspan="5" class="empty">loading…</td></tr></tbody>
+        </table>
+        <p class="note">GET routes are links — they open against this shunt.</p>
+    </div>
+
+    <div class="grid" style="margin-top: var(--space-6)">
+        <div>
+            <h2>Behaviour</h2>
+            <div class="panel">
+                <label>Random delays <input type="checkbox" id="enable_random_delays"></label>
+                <label>Min delay (ms) <input type="number" id="min_delay_ms" min="0"></label>
+                <label>Max delay (ms) <input type="number" id="max_delay_ms" min="0"></label>
+                <label>Error rate (0–1) <input type="number" id="error_rate" min="0" max="1" step="0.05"></label>
+                <label>Unknown id
+                    <select id="unknown_id">
+                        <option value="generate">generate</option>
+                        <option value="404">404</option>
+                    </select>
+                </label>
+                <label>Page size <input type="number" id="page_size" min="1"></label>
+                <div class="actions">
+                    <button type="button" id="save">Apply</button>
+                    <button type="button" id="reset">Reset data</button>
+                </div>
+                <p class="note">Applies immediately, in memory. Edit depot/config.json to persist.</p>
+            </div>
+        </div>
+
+        <div>
+            <h2>Stored rows</h2>
+            <div class="panel"><pre id="stats">loading…</pre></div>
+        </div>
+    </div>
+
+    <h2>Pinned responses</h2>
+    <div class="panel">
+        <pre id="responses">loading…</pre>
+        <p class="note">
+            Keys are <code>"METHOD /path"</code> and win over everything else.
+            Edit <code>depot/responses.json</code>, or POST to <code>/mock/responses</code>.
+        </p>
+    </div>
+
+    <script>
+    const KNOBS = ["enable_random_delays", "min_delay_ms", "max_delay_ms",
+                   "error_rate", "unknown_id", "page_size"];
+
+    async function get(path) {
+        const response = await fetch(path);
+        if (!response.ok) throw new Error(path + " -> " + response.status);
+        return response.json();
+    }
+
+    function cell(text) {
+        const td = document.createElement("td");
+        td.textContent = text == null ? "" : String(text);
+        return td;
+    }
+
+    async function loadRoutes() {
+        const [spec, stats] = await Promise.all([get("/mock/spec"), get("/mock/stats")]);
+        const body = document.querySelector("#routes tbody");
+        body.replaceChildren();
+
+        if (!spec.routes || !spec.routes.length) {
+            const row = document.createElement("tr");
+            const td = cell("no routes in spec.json");
+            td.colSpan = 5;
+            td.className = "empty";
+            row.appendChild(td);
+            body.appendChild(row);
+            return;
+        }
+
+        for (const route of spec.routes) {
+            const row = document.createElement("tr");
+
+            const verb = document.createElement("td");
+            const badge = document.createElement("span");
+            badge.className = "verb " + route.method;
+            badge.textContent = route.method;
+            verb.appendChild(badge);
+            row.appendChild(verb);
+
+            const path = document.createElement("td");
+            if (route.method === "GET" && !route.path.includes("{")) {
+                const link = document.createElement("a");
+                link.className = "route";
+                link.href = route.path;
+                link.textContent = route.path;
+                path.appendChild(link);
+            } else {
+                path.textContent = route.path;
+            }
+            row.appendChild(path);
+
+            row.appendChild(cell(route.operation));
+            row.appendChild(cell(route.model));
+            row.appendChild(cell(stats.calls[route.method + " " + route.path] || 0));
+            body.appendChild(row);
+        }
+    }
+
+    async function loadConfig() {
+        const config = await get("/mock/config");
+        for (const knob of KNOBS) {
+            const input = document.getElementById(knob);
+            if (!input) continue;
+            if (input.type === "checkbox") input.checked = Boolean(config[knob]);
+            else input.value = config[knob];
+        }
+    }
+
+    async function loadStats() {
+        const stats = await get("/mock/stats");
+        document.getElementById("stats").textContent = JSON.stringify(stats.rows, null, 2);
+    }
+
+    async function loadResponses() {
+        const pinned = await get("/mock/responses");
+        const target = document.getElementById("responses");
+        target.textContent = Object.keys(pinned).length
+            ? JSON.stringify(pinned, null, 2)
+            : "{}   — nothing pinned; responses come from the store, examples, or the generator";
+    }
+
+    document.getElementById("save").addEventListener("click", async () => {
+        const payload = {};
+        for (const knob of KNOBS) {
+            const input = document.getElementById(knob);
+            if (!input) continue;
+            if (input.type === "checkbox") payload[knob] = input.checked;
+            else if (input.type === "number") payload[knob] = Number(input.value);
+            else payload[knob] = input.value;
+        }
+        const response = await fetch("/mock/config", {
+            method: "POST",
+            headers: { "content-type": "application/json" },
+            body: JSON.stringify(payload),
+        });
+        if (!response.ok) {
+            alert("Could not apply: " + (await response.text()));
+            return;
+        }
+        await loadConfig();
+    });
+
+    document.getElementById("reset").addEventListener("click", async () => {
+        await fetch("/mock/reset", { method: "POST" });
+        await Promise.all([loadStats(), loadRoutes()]);
+    });
+
+    function refresh() {
+        return Promise.all([loadRoutes(), loadConfig(), loadStats(), loadResponses()])
+            .catch((error) => console.error(error));
+    }
+
+    refresh();
+    setInterval(() => Promise.all([loadRoutes(), loadStats()]).catch(() => {}), 5000);
+    </script>
+</body>
+</html>