Learning path
A curated path through API style, REST checklists, OpenAPI contracts, schema boundaries, authentication, scopes, HTTP behavior, error contracts, pagination, retries, HTTP caching, gateways, webhooks, and JSON tooling for maintainable backend APIs.
10 guides and tools
Choose API style, review REST contracts, document schemas, evolve versions, and understand where an API gateway and browser preflight behavior fit.
4 guides and tools
Design status codes, stable error shapes, request IDs, and client-friendly failure behavior.
5 guides and tools
Understand cache headers, choose Cache-Control policies, validate with ETags, operate through CDNs, and keep private responses out of shared caches.
10 guides and tools
Protect APIs with authentication choices, cookies vs tokens, API keys, OAuth scopes, service credentials, gateways, and clear auth failures.
5 guides and tools
Make API retries safer with idempotency, abuse prevention, rate limits, backoff, and predictable response contracts.
9 guides and tools
Handle paginated data, pagination metadata, webhook delivery, JSON contracts, schemas, and payload inspection.
Start here
These articles are the strongest entry points into the API design cluster.
API Design Jan 21, 2026 5 min read
Compare REST and RPC API styles through resources, actions, payload design, caching, versioning, and backend team workflows.
API Design Jul 1, 2026 6 min read
Use this REST API design checklist to review resources, methods, status codes, errors, pagination, idempotency, versioning, auth, and OpenAPI docs.
API Design Jun 30, 2026 4 min read
Compare PUT and PATCH in REST APIs, including replacement vs partial updates, idempotency, validation, status codes, and backend implementation choices.
API Design Jun 30, 2026 4 min read
Learn how OpenAPI describes REST APIs, including paths, operations, schemas, examples, auth, versioning, code generation, and contract review.
API Design Jul 25, 2026 7 min read
Model bearer tokens, API keys, OAuth 2.0, and OpenID Connect in OpenAPI with Springdoc and Express examples, overrides, tests, and enforcement boundaries.
API Design Jul 1, 2026 5 min read
Compare JSON Schema and OpenAPI Schema for backend API contracts, including validation, documentation, examples, tooling, and compatibility.
API Design Mar 22, 2026 5 min read
Understand the HTTP status codes backend developers use most often in REST APIs, including 200, 201, 400, 401, 404, 409, and 500.
API Design Jun 29, 2026 5 min read
Learn practical REST API error handling patterns, including status codes, stable error codes, field errors, request IDs, and safe messages.
API Design Jul 18, 2026 11 min read
Design RFC 9457 problem details for HTTP APIs with stable type URIs, safe extensions, validation errors, Spring Boot, and Node.js examples.
API Design Jul 26, 2026 10 min read
Understand Cache-Control, Age, Expires, Vary, freshness, validation, and browser versus shared cache behavior with Java and Node.js examples.
API Design Jul 26, 2026 10 min read
Choose safe API caching policies with max-age, s-maxage, private, no-cache, no-store, revalidation, and practical Java and Node.js recipes.
API Design Jul 26, 2026 6 min read
Implement ETag, If-None-Match, Last-Modified, 304 responses, and safe update preconditions with Spring Boot and Express examples.
API Design Jul 26, 2026 8 min read
Design safe CDN cache keys, shared TTLs, revalidation, stale responses, and invalidation workflows for Java and Node.js APIs.
API Design Jul 26, 2026 8 min read
Protect authenticated and personalized API responses from browser and shared-cache leaks with safe Java and Node.js policies and tests.
API Design Jun 28, 2026 5 min read
Learn practical API versioning strategies, including URL versions, header versions, backward compatibility, deprecation, and migration plans.
API Design Jul 18, 2026 11 min read
Use RFC 9745 Deprecation, deprecation links, and Sunset headers to communicate API lifecycle dates, migration guidance, and removal plans.
Backend Jul 2, 2026 5 min read
Learn how CORS preflight requests work, including OPTIONS handling, allowed methods, headers, credentials, caching, errors, and backend mistakes.
API Design Mar 29, 2026 6 min read
Learn what idempotency means in API design, why retries create duplicate actions, and how idempotency keys protect backend workflows.
API Design Apr 5, 2026 5 min read
Compare offset, cursor, and keyset pagination for REST APIs, including tradeoffs, response shapes, sorting, and backend performance.
API Design Jul 18, 2026 7 min read
Build cursor pagination with stable sorting, keyset SQL, opaque signed tokens, filter binding, error handling, and Java and Node.js implementations.
API Design Jul 1, 2026 5 min read
Learn how to design pagination metadata for REST APIs, including pageInfo, cursors, hasNextPage, limits, totals, links, sorting, and compatibility.
Backend Jul 2, 2026 6 min read
Learn API authentication best practices, including tokens, API keys, OAuth, mTLS, sessions, gateways, rotation, scopes, errors, and logging.
Backend Jul 2, 2026 6 min read
Compare cookie and token authentication for backend apps, including sessions, JWTs, CSRF, XSS, storage, CORS, mobile clients, and API tradeoffs.
Backend Jul 2, 2026 4 min read
Learn OAuth scopes for backend APIs, including permissions, consent, least privilege, access tokens, naming, validation, and common mistakes.
Backend Jul 2, 2026 5 min read
Learn the OAuth client credentials flow for service-to-service APIs, including clients, secrets, scopes, tokens, rotation, and security risks.
Backend Jul 2, 2026 5 min read
Learn service accounts for backend systems, including machine identity, API access, least privilege, secrets, rotation, audit logs, and risks.
Backend Jul 2, 2026 5 min read
Learn API abuse prevention for backend systems, including rate limits, authentication signals, quotas, bot patterns, logging, errors, and gateways.
API Design Jun 28, 2026 5 min read
Learn how API rate limiting works, including fixed windows, sliding windows, token buckets, 429 responses, headers, and backend tradeoffs.
API Design Jul 18, 2026 10 min read
Learn how API rate limit headers communicate quotas, remaining capacity, retry timing, and client behavior across current and legacy formats.
API Design Jun 29, 2026 5 min read
Learn what an API gateway does in backend architecture, including routing, authentication, rate limiting, observability, and tradeoffs.
API Design Jun 29, 2026 4 min read
Learn how webhooks work in backend systems, including event delivery, signatures, retries, idempotency, and common design mistakes.
API Design Jun 30, 2026 5 min read
Learn how webhook signature verification works, including HMAC headers, raw request bodies, timestamps, replay protection, secret rotation, and safe failures.
Related tools
Use these browser-based tools while reviewing payloads, response contracts, IDs, and logs.
Available tool
Search common HTTP status codes locally in your browser with REST API usage notes, retry guidance, and backend examples.
Open toolAvailable tool
Generate a starter JSON Schema from example JSON locally in your browser for API contracts, validation, tests, and documentation.
Open toolAvailable tool
Generate TypeScript interfaces or type aliases from JSON locally in your browser for API responses, fixtures, and backend contracts.
Open toolAvailable tool
Test common JSONPath expressions against JSON locally in your browser for API debugging, fixtures, logs, and documentation.
Open toolAvailable tool
Resolve RFC 6901 JSON Pointers against JSON locally in your browser for OpenAPI, JSON Schema, JSON Patch, and API debugging.
Open toolAvailable tool
Generate UUID v4 values locally in your browser for request IDs, idempotency keys, database records, and test data.
Open toolAvailable tool
Convert Unix timestamps to UTC and local dates, or convert date strings to seconds and milliseconds locally in your browser.
Open toolHow to study
Strong API design is not only endpoint naming. It is the contract clients rely on: request shape, response shape, schemas, status codes, retry behavior, pagination metadata, versioning, and integration failure modes.
Start with API style and response behavior, then move into reliability topics such as idempotency, rate limiting, retries, and webhook delivery.
For adjacent backend architecture topics, browse the System Design Learning Path.
FAQ
Start with REST vs RPC, a REST API design checklist, OpenAPI schemas, HTTP status codes, stable error responses, versioning, pagination, idempotency, and HTTP caching. Those topics shape most long-lived backend APIs.
No. REST is common for public HTTP APIs, but RPC, gRPC, event-driven APIs, and webhooks are also useful depending on the workflow and clients.
Unstable response shapes, unclear error codes, unsafe retries, missing idempotency, weak pagination rules, and breaking changes without migration plans are common sources of pain.
The tools help inspect status codes, generate schema or TypeScript drafts, resolve JSON paths, create request IDs, and debug timestamps while designing or reviewing APIs.
