Topic
REST API
11 engineering lessons and 16 supporting resources about REST API.
About this topic
This track collects 11 lessons on REST API, written to be read in order and revisited as reference.
It opens with “What Makes an API RESTful? REST Constraints.” What makes an API RESTful? Learn Roy Fielding's six REST constraints — statelessness, uniform interface, HATEOAS, cacheability — and how to nail the interview answer.
You’ll learn
- What Makes an API RESTful? REST Constraints
- HTTP Methods & Status Codes Explained
- API Idempotency & Safe Retries
- REST Resource Modeling & URI Design
- REST API Versioning Strategies
Recommended starting lessons
View all lessons- 01What Makes an API RESTful? REST Constraints
What makes an API RESTful? Learn Roy Fielding's six REST constraints — statelessness, uniform interface, HATEOAS, cacheability — and how to nail the interview answer.
5 min - 02HTTP Methods & Status Codes Explained
HTTP methods and status codes explained: GET, POST, PUT, PATCH, DELETE semantics, safe vs idempotent methods, and choosing the right 2xx/4xx/5xx code for REST APIs.
5 min - 03API Idempotency & Safe Retries
API idempotency explained: how idempotency keys make POST retries safe, dedupe duplicate requests, and survive network failures without double-charging in REST APIs.
4 min
Resources in this track
Curated references, cheat sheets, and checklists.
- API Design Interview Framework
An 11-step framework for whiteboarding a REST API design in interviews — from requirements through resource modeling, idempotency, caching, versioning, auth, and trade-offs.
- API Security & Auth Cheat Sheet
A REST cheat sheet on authentication vs authorization, and the credential schemes — API keys, bearer tokens, OAuth2/OIDC, mTLS — and where each fits.
- Caching, Pagination & Versioning Cheat Sheet
A REST cheat sheet on Cache-Control directives and conditional requests, pagination strategies, and API versioning and evolution at a glance.
- Idempotency & Retries Cheat Sheet
A REST cheat sheet on safe vs idempotent HTTP methods, method idempotency at a glance, and using an Idempotency-Key to make POST retries safe.
- REST Constraints & Maturity — Cheat Sheet
A REST cheat sheet on the six architectural constraints, the Richardson maturity model, HATEOAS, and HTTP method semantics — quick reference for API interviews.