Live APIBackend API design
customizable caching api
A REST API for configurable cache behavior, size limits, documentation, and predictable invalidation.
Problem
Caching logic often ends up scattered through applications. This project isolates cache operations behind a clear API with constraints and documentation.
Architecture
- Express routes expose cache create, read, update, and delete operations.
- Redis handles fast key-value access and expiration behavior.
- PostgreSQL and Prisma support persisted metadata where needed.
- API documentation gives consumers a direct way to inspect behavior.
Key decisions
- Kept the API RESTful so behavior is easy to test with common tooling.
- Added size constraints to make cache behavior explicit instead of unbounded.
- Documented endpoints alongside the deployed API to reduce integration friction.
Tradeoffs
- A generic cache API is flexible, but product-specific cache rules still need application-level decisions.
- Redis improves response time, but operational correctness depends on expiration and invalidation design.
What I learned
- Good cache systems need constraints as much as speed.
- Documentation is part of the backend interface, not a separate afterthought.
Stack
Node.jsExpress.jsPostgreSQLPrisma ORMREST APIRedis