# Codex Pass 01 — Backend Foundation

## Goal

Create the FastAPI backend foundation without business shortcuts.

## Must implement

- backend package layout following repository conventions;
- FastAPI app factory or app entrypoint;
- health endpoint;
- settings loader from environment;
- structured error response shape;
- basic logging config;
- test skeleton;
- backend README update.

## Must not implement

- dataset processing;
- AI inference;
- authentication;
- frontend work;
- live external services.

## Acceptance

- backend imports successfully;
- health endpoint returns service status;
- tests include import/smoke test;
- `.env.example` remains authoritative.

## Output

Use `docs/M6_FINAL_HANDOFF_TEMPLATE.md`.