How React Context actually works: create a provider, read it with useContext, avoid the re-render trap, and know when Context beats Redux and when it loses.
Fetch data in React without the usual bugs: race conditions in useEffect, AbortController cleanup, and what SWR and TanStack Query actually cache for you.
Learn React with TypeScript from scratch: type components and props, manage state with useState, write generic components, and set up a project with Vite.
Compare React state management libraries: Zustand, Jotai, Recoil, Valtio, and Redux Toolkit. When to use each, plus useReducer and Context API trade-offs.