⚙️ Backend Essentials

Design REST APIs that make sense: pick methods by semantics, return the right status codes, and stay stateless with clean versioning and pagination.

Lock down your services the right way: hash passwords with bcrypt or argon2, handle tokens and sessions correctly, and shut out CSRF and injection.

Keep your data correct under pressure with connection pools, transactions, reversible migrations, and joins that kill the dreaded N+1 query.

Slash latency and database load by caching hot reads, then master the hard part — invalidation — alongside indexing and pagination that scale.

Keep requests snappy by pushing slow work onto queues, then survive at-least-once delivery with idempotent consumers, dead-letter queues, and backpressure.

Build services that stay up: rate limits, backoff-with-jitter retries, timeouts, and circuit breakers, all made observable with logs, metrics, and traces.