Flask

This is your go-to for building REST APIs and microservices in Python when you want control over your stack without Django's overhead. The skill covers the application factory pattern for production apps, blueprints for organizing routes into modules, and Flask-SQLAlchemy integration for database work. It includes practical patterns for request handling, error responses, and pagination. Flask shines when you need something lightweight that gets out of your way, and this skill gives you the working patterns rather than just hello world examples. The blueprint structure alone will save you from messy monolithic app.py files as your API grows.