Backend & APIs

Popular 13 guides published

REST, HTTP methods, authentication, webhooks, CORS — how servers talk and why your API calls fail at 2am. Every concept explained starting from what AI actually generates.

Start: What Is an API? → Fix That CORS Error

API Foundations

🔌 APIs

What Is an API?

The beginner's guide for AI-assisted developers — when AI "gets weather data," here's exactly what it's doing and how to fix it when it breaks.

Start Here
🔌 REST

What Is a REST API?

HTTP methods, status codes, and fetch() explained — why 90% of AI-generated backends are REST and what that actually means.

Popular
🔌 HTTP

What Are HTTP Status Codes?

200, 404, 500, 401, 403 — a vibe coder's guide to API responses. What each code means and how to handle them in AI-generated code.

Beginner
⚙️ Backend

What Is Middleware?

Express & Next.js middleware explained for AI coders — what runs before your route handler and why AI always adds app.use().

Beginner
🔔 Events

What Is a Webhook?

Event-driven APIs explained for AI coders — Stripe payments, GitHub events, Slack bots. How to receive them and what can go wrong.

Intermediate
📊 GraphQL

What Is GraphQL?

The alternative to REST — queries, mutations, and why AI sometimes generates GraphQL instead of REST endpoints.

Intermediate
⚡ Real-Time

What Are WebSockets?

Real-time communication for AI-built apps — chat, live updates, and collaborative features. How WebSockets work and when to use them.

Intermediate

Authentication & Security

🔐 Auth

What Is Authentication?

Login systems explained for AI coders — sessions, tokens, cookies, and why "it works on localhost" but breaks in production.

Popular
🔑 JWT

What Is a JWT?

JSON Web Tokens explained — how AI implements stateless authentication, what's in that eyJh... string, and when JWTs are the wrong choice.

Intermediate
🔑 OAuth

What Is OAuth?

"Sign in with Google" explained for AI coders — the OAuth flow, access tokens, refresh tokens, and common AI implementation mistakes.

Intermediate
🚦 Security

What Is Rate Limiting?

Protecting your API from abuse — what rate limiting is, how to implement it in AI-generated Express/Next.js apps, and what happens without it.

Intermediate

The CORS Problem (It Happens to Everyone)

🌐 CORS

What Is CORS?

The complete guide — why the browser blocks your API calls, what the Access-Control headers mean, and how to configure it correctly.

Popular
🌐 CORS

What Is a CORS Error? How to Fix It

The most common AI-coder headache. Step-by-step fix guide for Express, Next.js, FastAPI, and any framework AI builds for you.

Fix Guide

Your Backend Needs a Database

Learn where AI stores your data and how to work with it safely.

Databases →