Staffcoder

Staffcoder is a hands-on coding platform where developers practice real engineering work instead of algorithm puzzles. It offers 1000+ challenges across 39 learning paths covering frameworks such as React, Next.js, Django, and Spring Boot, plus tooling like Docker and Kubernetes. Every challenge runs in a full browser IDE with a real terminal, file system, and live preview, so nothing needs to be installed. It is free to start.