Developer guides that go all the way down.
11 open-source guides, 214+ chapters. Each one starts at “what is this” and ends somewhere you could ship from — with the pitfalls, the interview questions, and the parts most tutorials skip.
- chapters
- 214+ chapters
- for every guide
- PDF for every guide
- MIT licensed
- Open source MIT licensed
All guides
JavaScript
The language itself — closures, prototypes, the event loop, and the async model everything else is built on.
TypeScript
Types that catch real bugs — generics, narrowing, utility types, and how to model a domain properly.
React
Hooks from useState to useReducer, custom hooks, memoization, error boundaries, and testing.
Next.js
The App Router as of Next.js 16 — Server Components, Server Actions, Cache Components, and PPR.
Node.js & Express
Servers, middleware, REST design, auth, file uploads, and talking to a database from Node.
SQL & Databases
Schema design, joins that make sense, indexes, transactions, and queries that stay fast.
Git & GitHub
Branching, rebase vs merge, conflict resolution, bisect, reflog recovery, and Actions.
Data Structures & Algorithms
The structures and patterns interviews actually ask about, with worked solutions.
Tailwind CSS
Utility-first styling, design tokens, responsive patterns, and building a component API.
System Design
Scaling from one box to many — load balancing, caching, queues, consistency, and the tradeoffs interviews probe.
Networking & Linux
The shell, permissions, processes, DNS, SSH, firewalls, and debugging a server that won't respond.