// Topic cluster · 5 live guides
APIs, databases, authentication, CI/CD, observability, deployment, and reliable product operations.
Protect expensive API work with scoped atomic limits, bounded concurrency, request cost, clear 429 responses, and a deliberate policy for limiter outages.
Separate cookie transport from JWT token format, then choose a session design around revocation, browser threats, validation, logout, and access boundaries.
Design PostgreSQL ownership, constraints, timestamps, relationships, and query-driven indexes, then plan migrations that preserve existing application behavior.
Compare GraphQL and REST using real client data shapes, backend cost, authorization, caching, pagination, and the team's ability to operate each contract.
Design REST endpoints around resource ownership, HTTP semantics, validation, pagination, safe retries, and errors that clients can act on without leaking internals.