Koa Middleware Chain

A guide to building elegant APIs using Koa's onion-model middleware cascade with async/await.

Usage

Ask about Koa middleware patterns, context manipulation, error handling, or API composition.

Examples

• "Create a logging middleware that captures response time"
• "How does Koa's onion model differ from Express?"
• "Build error handling middleware with Koa"

Guidelines

• Always await next() to ensure downstream middleware executes
• Use ctx.state for passing data between middleware
• Handle errors with try/catch around await next()
• Keep the middleware chain order meaningful
• Use koa-compose for grouping related middleware