Interview Practice Pick a track, then choose your difficulty and number of questions . Each round is a random mix of multiple-choice and code-completion challenges, with instant feedback and model answers.
⚛️ React.js Hooks, components, state, rendering, performance. 100 questions · choose → 🟨 JavaScript Closures, this, async, prototypes, the event loop. 100 questions · choose → ☕ Java OOP, collections, generics, streams, concurrency, the JVM. 100 questions · choose → 🌱 Spring Boot DI, beans, MVC, Spring Data JPA, transactions, security. 100 questions · choose → ▲ Next.js App Router, Server Components, data fetching, caching, Server Actions, middleware. 100 questions · choose → 🐹 Go Slices, maps, interfaces, goroutines, channels, errors, the runtime. 100 questions · choose →