mycodedojo · est. 2020
Field notes from the code dojo.
Homelab, self-hosting, AI agents and full-stack craft. I'm Michael Cooper, a senior full-stack engineer who runs most of his stack on hardware in his own house. These are the notes I write while I train.
Featured note
React 19: The New APIs Worth Using Right Now
React 19 shipped the most significant API additions in years. Here is a practical tour of the ones that change how you write components day-to-day.
Fresh off the mat
Latest notes
Next.js Middleware: Auth Guards, Redirects, and Edge Logic
Middleware runs before every matched request at the Edge, making it the right place for auth gating, locale detection, and fast redirects without touching your page code.
Green belt
React Suspense and Error Boundaries: Declarative Loading and Error States
Replace scattered isLoading and error checks with Suspense and Error Boundaries — a cleaner model for async UI in React.
Green belt
TIL: findLast() and findLastIndex() — Search Arrays From the End
ES2023 added findLast() and findLastIndex() so you can stop reversing arrays just to find the last matching element.
White belt
Custom React Hooks: Extract, Reuse, and Actually Test Them
Custom hooks are React's best composability tool — here is how to design them well, avoid the common pitfalls, and write tests that give you real confidence.
Green belt
TypeScript Utility Types: The Ones You Will Actually Use
Partial, Pick, Omit, ReturnType, Awaited — six built-in TypeScript helpers that eliminate repetitive type definitions and make refactors painless.
Yellow belt
Core Web Vitals in Next.js: Measuring and Fixing What Actually Matters
LCP, INP, and CLS explained with concrete Next.js fixes — next/image, font optimization, lazy loading, and the useReportWebVitals hook.
Green belt