Practise by debugging skill.
Each track maps ready incidents and planned Debugging 50 patterns by topic. Planned entries are roadmap only — not playable.
Open Source Debugging
Repo navigation, failing test reproduction, minimal patch reasoning, and PR explanation — trained on real public bug-fix history.
Config & Environment
Debug missing environment variables, config drift, filesystem assumptions, and tenant-specific runtime settings.
HTTP/API
Practice request contracts, headers, pagination, parsing, CORS behavior, and API edge cases.
Secrets & Auth
Investigate auth headers, IAM failures, rotated secrets, webhook signatures, and authorization regressions.
Network & Connectivity
Debug timeouts, ports, routing, service health, and retry behavior across service boundaries.
Caching & Performance
Find stale keys, stampedes, tenant cache bleed, feature flag drift, and performance regressions.
Database
Work through query behavior, serialization issues, transactions, soft deletes, and consistency failures.
CI/CD & Pipelines
Practice deploy locks, migrations, artifacts, poisoned caches, and release-pipeline regressions.
Testing & Reliability
Debug flaky checks, retries, hidden validation failures, test isolation, and incident recovery patterns.
Date/Time
Fix timezone, DST, expiry, unit mismatch, and time-window bugs that only appear at boundaries.
Concurrency
Practice stale locks, duplicate workers, race conditions, async cleanup, and atomicity failures.
Deployment
Debug broken health checks, missing container env, target-port mismatches, and rollout regressions.