Lazy Bird mascot

Lazy Bird catches the bug

but is too lazy to fix it.



A hands-on learning platform with intentionally broken systems. Clone, run, debug, and fix real-world performance problems.

Self-Contained
Docker-first environments ready to run
Real Problems
Database, concurrency, event-driven issues
Learn by Fixing
Diagnose, understand, and solve

Broken Systems

Data Integrity

Flash Sales

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Database Performance

Employee Directory

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Asynchronous Patterns

Product Catalog

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Explore All Systems 5 systems available