CTFd Development & Operations

CTFd is a Python 3.11 Flask-based Capture The Flag platform. SQLAlchemy 1.4, Redis, Jinja2 themes, plugin system.

When to Use

• Developing CTFd plugins (custom challenge types, scoring, auth)
• Debugging CSRF 302 errors, API 500 responses, or session issues
• Standing up or modifying the Docker Compose stack (nginx, MySQL, Redis)
• Customizing Jinja2 themes or static assets
• Writing pytest tests against CTFd's Flask test infrastructure
• Running database migrations with SQLAlchemy 1.4
• Diagnosing nginx reverse proxy misconfigurations

When NOT to Use

• Other CTF platforms (CTFx, FBCTF) — different codebases
• General Flask development unrelated to CTFd