New: Build Your Own Redis Challenge

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Complex Systems

Master programming fundamentals by recreating real-world tools from scratch. Build Redis, Git, Docker, and more with hands-on, CLI-driven challenges.

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🔴

Build Your Own Redis

Intermediate

Implement a Redis server from scratch, supporting PING, GET, SET, and more commands.

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📦

Build Your Own Git

Advanced

Create a Git implementation supporting init, add, commit, and branching.

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🌐

Build Your Own HTTP Server

Beginner

Build an HTTP/1.1 server that handles requests, routing, and file serving.

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Local Development

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Cloud Sandbox

$5 /month

Perfect if you want to skip the local environment setup.

  • ✓ Run & test code in the browser
  • ✓ Zero local setup required
  • ✓ Cloud-persistent workspaces

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