Practice the judgment real engineering work requires.
Fix bugs, review risky changes, understand unfamiliar systems, diagnose failing pipelines, investigate incidents, or sharpen your instincts in a short round.
Full Debugging Labs
Work inside complete challenge environments: reproduce the failure, patch the code, and validate the fix.
Core Labs
20 playable · 35 planned
Practice backend, platform, reliability, API, config, cache, and deployment failures in isolated codebases.
Open →Open Source Labs
5 playable · 5 drafts
Debug regressions derived from public OSS history. Playable labs are reviewed; packaging drafts stay locked.
Open →Company Prep
Pattern-based tracks
Practice company-style engineering failure patterns. These tracks are curated, unofficial, and unaffiliated.
Open →Failure Entry Modes
Start from the evidence engineers often receive before they know where the bug lives.
Review Lab
3 PR-style review cases
Catch risky changes in fictional, pattern-based pull requests before they merge.
Open →Codebase Navigator
3 navigation drills
Trace requests, configuration, and ownership in curated unfamiliar-system snapshots.
Open →CI Red
3 failed pipeline runs
Diagnose curated CI-style failures from logs and config. Nothing connects to an external CI system.
Open →Incident Labs
3 production-style incidents
Investigate fictional incidents from logs, metrics, traces, and config. No live systems or customer data.
Open →Fast Practice
Build pattern recognition in short rounds. Progress for these modes is saved locally on this device.