python-fastapi-development – Coding skill for AI agents

Python/FastAPI Development Workflow

Overview

Specialized workflow for building production-ready Python backends with FastAPI, featuring async patterns, SQLAlchemy ORM, Pydantic validation, and comprehensive API patterns.

When to Use This Workflow

Use this workflow when:

• Building new REST APIs with FastAPI
• Creating async Python backends
• Implementing database integration with SQLAlchemy
• Setting up API authentication
• Developing microservices

Workflow Phases

Phase 1: Project Setup

Skills to Invoke

• app-builder - Application scaffolding
• python-development-python-scaffold - Python scaffolding
• fastapi-templates - FastAPI templates
• uv-package-manager - Package management

Actions

1. Set up Python environment (uv/poetry)

2. Create project structure

3. Configure FastAPI app

4. Set up logging

5. Configure environment variables

Copy-Paste Prompts

Use @fastapi-templates to scaffold a new FastAPI project

Use @python-development-python-scaffold to set up Python project structure

Phase 2: Database Setup

Skills to Invoke

• prisma-expert - Prisma ORM (alternative)
• database-design - Schema design
• postgresql - PostgreSQL setup
• pydantic-models-py - Pydantic models

Actions

1. Design database schema

2. Set up SQLAlchemy models

3. Create database connection

4. Configure migrations (Alembic)

5. Set up session management

Copy-Paste Prompts

Use @database-design to design PostgreSQL schema

Use @pydantic-models-py to create Pydantic models for API

Phase 3: API Routes

Skills to Invoke

• fastapi-router-py - FastAPI routers
• api-design-principles - API design
• api-patterns - API patterns

Actions

1. Design API endpoints

2. Create API routers

3. Implement CRUD operations

4. Add request validation

5. Configure response models

Copy-Paste Prompts

Use @fastapi-router-py to create API endpoints with CRUD operations

Use @api-design-principles to design RESTful API

Phase 4: Authentication

Skills to Invoke

• auth-implementation-patterns - Authentication
• api-security-best-practices - API security

Actions

1. Choose auth strategy (JWT, OAuth2)

2. Implement user registration

3. Set up login endpoints

4. Create auth middleware

5. Add password hashing

Copy-Paste Prompts

Use @auth-implementation-patterns to implement JWT authentication

Phase 5: Error Handling

Skills to Invoke

• fastapi-pro - FastAPI patterns
• error-handling-patterns - Error handling

Actions

1. Create custom exceptions

2. Set up exception handlers

3. Implement error responses

4. Add request logging

5. Configure error tracking

Copy-Paste Prompts

Use @fastapi-pro to implement comprehensive error handling

Phase 6: Testing

Skills to Invoke

• python-testing-patterns - pytest testing
• api-testing-observability-api-mock - API testing

Actions

1. Set up pytest

2. Create test fixtures

3. Write unit tests

4. Implement integration tests

5. Configure test database

Copy-Paste Prompts

Use @python-testing-patterns to write pytest tests for FastAPI

Phase 7: Documentation

Skills to Invoke

• api-documenter - API documentation
• openapi-spec-generation - OpenAPI specs

Actions

1. Configure OpenAPI schema

2. Add endpoint documentation

3. Create usage examples

4. Set up API versioning

5. Generate API docs

Copy-Paste Prompts

Use @api-documenter to generate comprehensive API documentation

Phase 8: Deployment

Skills to Invoke

• deployment-engineer - Deployment
• docker-expert - Containerization

Actions

1. Create Dockerfile

2. Set up docker-compose

3. Configure production settings

4. Set up reverse proxy

5. Deploy to cloud

Copy-Paste Prompts

Use @docker-expert to containerize FastAPI application

Technology Stack

| Category | Technology |

|----------|------------|

| Framework | FastAPI |

| Language | Python 3.11+ |

| ORM | SQLAlchemy 2.0 |

| Validation | Pydantic v2 |

| Database | PostgreSQL |

| Migrations | Alembic |

| Auth | JWT, OAuth2 |

| Testing | pytest |

Quality Gates

• [ ] All tests passing (>80% coverage)
• [ ] Type checking passes (mypy)
• [ ] Linting clean (ruff, black)
• [ ] API documentation complete
• [ ] Security scan passed
• [ ] Performance benchmarks met

Related Workflow Bundles

• development - General development
• database - Database operations
• security-audit - Security testing
• api-development - API patterns

Limitations

• Use this skill only when the task clearly matches the scope described above.
• Do not treat the output as a substitute for environment-specific validation, testing, or expert review.
• Stop and ask for clarification if required inputs, permissions, safety boundaries, or success criteria are missing.