03. APIs and Services

Goal

Create consistent APIs with clear contracts and predictable behavior.

What to learn

• REST conventions and resource modeling.
• Request validation and response standards.
• Authentication and authorization basics.
• Logging and structured errors.
• API testing with automated checks.

Deliverables

• A CRUD API for one project domain.
• API docs for endpoints and payloads.
• Test suite covering critical routes.

Exit criteria

You can build, document, and test an API that a frontend can consume without guesswork.