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name: oe-backend-startup-triage description: Debug “backend won’t start / first request 500 / ports stuck” quickly. Use when uvicorn reload behaves strangely, ports 8000/3000 are blocked, or you see first-request errors like “unexpected keyword argument” due to stale bytecode caches.

oe-backend-startup-triage

Preferred startup path

1. Use the canonical dev script (port cleanup + key loading):

   • ./scripts/dev_server.sh start

2. If the frontend is stuck (white page / endless spinner), clear zombie processes:

   • kill -9 $(lsof -nP -iTCP:3000 -sTCP:LISTEN -t)
   • cd atelier-ai-frontend && npm run dev

If port 8000 is stuck

• Identify and kill listeners:
  • lsof -nP -iTCP:8000 -sTCP:LISTEN
  • lsof -nP -tiTCP:8000 -sTCP:LISTEN | xargs kill -9

If the first request fails with “unexpected keyword argument …”

This is usually stale .pyc / __pycache__ from changed dataclasses.

1. Clear bytecode caches:

   • find backend -name "*.pyc" -delete
   • find backend -type d -name "__pycache__" -exec rm -rf {} +

2. Restart with bytecode disabled:

   • export PYTHONDONTWRITEBYTECODE=1
   • ./scripts/dev_server.sh start

If imports fail (ImportError / missing export)

1. Run the compile/import sanity gate:

   • python3 scripts/verify_refactor.py

2. If the failure is in a workflow wrapper, ensure the wrapper re-exports the referenced symbol (see docs/guides/TEAM_GUIDE.md for prior “missing export” regressions).