phase 3

core/api/detect/config.py

@@ -64,6 +64,22 @@ def list_profiles():
     return [{"name": name} for name in _PROFILES]
 
 
+@router.get("/config/profiles/{profile_name}/pipeline")
+def get_pipeline_config(profile_name: str):
+    """Return the pipeline composition for a profile."""
+    from detect.profiles import get_profile
+    from fastapi import HTTPException
+    from dataclasses import asdict
+
+    try:
+        profile = get_profile(profile_name)
+    except ValueError:
+        raise HTTPException(status_code=404, detail=f"Unknown profile: {profile_name}")
+
+    config = profile.pipeline_config()
+    return asdict(config)
+
+
 @router.get("/config/stages", response_model=list[StageConfigInfo])
 def list_stage_configs():
     """Return the stage palette with config field metadata for the editor."""

core/api/detect/run.py

@@ -88,7 +88,7 @@ def run_pipeline(req: RunRequest):
         log_level=req.log_level,
     )
 
-    pipeline = get_pipeline(checkpoint=req.checkpoint)
+    pipeline = get_pipeline(checkpoint=req.checkpoint, profile_name=req.profile_name)
 
     initial_state = DetectState(
         video_path=local_path,

core/schema/models/__init__.py

@@ -35,6 +35,7 @@ from .detect import DETECT_VIEWS  # noqa: F401 — discovered by modelgen generi
 from .inference import INFERENCE_VIEWS  # noqa: F401 — GPU inference server API types
 from .ui_state import UI_STATE_VIEWS  # noqa: F401 — UI store state types
 from .stages import StageConfigField, StageIO, StageDefinition, STAGE_VIEWS  # noqa: F401
+from .pipeline_config import StageRef, Edge, PipelineConfig, PIPELINE_CONFIG_VIEWS  # noqa: F401
 from .detect_api import RunRequest, RunResponse, DETECT_API_VIEWS  # noqa: F401
 from .views import ChunkEvent, ChunkOutputFile, PipelineStats, WorkerEvent
 from .sources import ChunkInfo, SourceJob, SourceType

core/schema/models/pipeline_config.py

@@ -0,0 +1,46 @@
+"""
+Pipeline composition config — source of truth for graph topology.
+
+Defines what stages run, in what order, with what branching.
+Belongs to a profile. Persisted as JSONB.
+
+The execution strategy (serial, parallel, distributed) is separate —
+the runner reads this config and flattens it into a sequence for now.
+"""
+
+from dataclasses import dataclass, field
+from typing import Any, Dict, List, Optional
+
+
+@dataclass
+class StageRef:
+    """Reference to a stage in the pipeline graph."""
+    name: str                          # stage name (matches StageDefinition.name)
+    branch: str = "trunk"              # which branch this belongs to
+    execution_target: str = "local"    # local | gpu | lambda | gcp
+
+
+@dataclass
+class Edge:
+    """Connection between stages in the graph."""
+    source: str        # stage name
+    target: str        # stage name
+    condition: str = ""  # empty = unconditional, otherwise a routing rule key
+
+
+@dataclass
+class PipelineConfig:
+    """
+    Pipeline graph topology + routing rules.
+
+    Holder model — stages/edges define the graph shape,
+    routing_rules is a JSONB blob for decision tree logic.
+    """
+    name: str
+    profile_name: str
+    stages: List[StageRef] = field(default_factory=list)
+    edges: List[Edge] = field(default_factory=list)
+    routing_rules: Dict[str, Any] = field(default_factory=dict)
+
+
+PIPELINE_CONFIG_VIEWS = [StageRef, Edge, PipelineConfig]