---
phase: 01-core-infrastructure-security
plan: 01
subsystem: infra
tags: [fastapi, pydantic, uvicorn, python, uv]

# Dependency graph
requires: []
provides:
  - FastAPI application entry point
  - pydantic-settings configuration management
  - Health check endpoints at /health and /api/v1/health
  - Project dependencies via uv
affects: [01-02, 01-03, 01-04, 01-05]

# Tech tracking
tech-stack:
  added: [fastapi, uvicorn, sqlalchemy, asyncpg, pydantic, pydantic-settings, alembic, slowapi, fastapi-csrf-protect, ruff, mypy, pytest]
  patterns: [pydantic-settings for config, environment-based docs toggle, versioned API routes]

key-files:
  created:
    - pyproject.toml
    - .env.example
    - README.md
    - backend/app/main.py
    - backend/app/core/config.py
    - backend/app/api/v1/router.py
    - backend/app/api/v1/endpoints/health.py
  modified: []

key-decisions:
  - "Used hatchling as build backend for pyproject.toml"
  - "Created root /health endpoint outside versioned API for simple health checks"
  - "Configured ruff with E, F, I, N, W, UP rule sets"

patterns-established:
  - "Versioned API at /api/v1 prefix"
  - "Health endpoints with /health (basic) and /health/ready (readiness)"
  - "Environment-based feature toggling (docs disabled in production)"

# Metrics
duration: 3min
completed: 2026-01-25
---

# Phase 01 Plan 01: FastAPI Backend Foundation Summary

**FastAPI backend initialized with uv package manager, pydantic-settings configuration, and health endpoints at /health and /api/v1/health**

## Performance

- **Duration:** 3 min
- **Started:** 2026-01-25T20:06:07Z
- **Completed:** 2026-01-25T20:09:42Z
- **Tasks:** 2
- **Files modified:** 13

## Accomplishments

- Initialized Python project with uv package manager and all required dependencies
- Created FastAPI application with production-ready configuration management
- Implemented health check endpoints with readiness probe placeholder
- Configured ruff linter passing on all code

## Task Commits

Each task was committed atomically:

1. **Task 1: Initialize Python project with uv and dependencies** - `300b3dd` (feat)
2. **Task 2: Create FastAPI application structure with health endpoint** - `519333e` (feat)

## Files Created/Modified

- `pyproject.toml` - Project configuration with dependencies, ruff, and mypy settings
- `.env.example` - Documented environment variables template
- `README.md` - Basic development setup instructions
- `backend/app/main.py` - FastAPI application entry point with root health check
- `backend/app/core/config.py` - pydantic-settings configuration with environment parsing
- `backend/app/api/v1/router.py` - API v1 router including health endpoints
- `backend/app/api/v1/endpoints/health.py` - Health and readiness check endpoints

## Decisions Made

- Used hatchling as build backend (standard for modern Python projects)
- Created root `/health` endpoint outside versioned API for simpler health checks
- Used pydantic-settings `model_config` approach (Pydantic v2 style) for configuration
- Configured comprehensive ruff rule sets: E (errors), F (pyflakes), I (isort), N (naming), W (warnings), UP (upgrades)

## Deviations from Plan

None - plan executed exactly as written.

## Issues Encountered

- uv was not installed initially - installed via curl script (expected for fresh environment)
- hatchling required README.md to exist - created minimal README.md file
- hatchling needed explicit package path - added `[tool.hatch.build.targets.wheel]` configuration

## User Setup Required

None - no external service configuration required.

## Next Phase Readiness

- FastAPI application structure is complete and verified
- Ready for Plan 01-02: PostgreSQL database setup and connection pooling
- Configuration management is in place for database URL and other settings

---
*Phase: 01-core-infrastructure-security*
*Completed: 2026-01-25*