Troubleshooting
Start with the smallest reproducible user workflow and the earliest failing boundary.
Diagnostic Sequence
1. Confirm the release version and intended environment. 2. Check the safe user-facing error and correlation identifier. 3. Verify configuration presence without printing secret values. 4. Confirm database and external-service reachability with least-privilege credentials. 5. Review access-controlled logs around the same correlation identifier. 6. Reproduce in a representative non-production environment. 7. Verify the fix and an adjacent workflow before promotion.
Avoid world-writable permissions, disabled authorization, exposed debug output, edited historical migrations, or copied production data as shortcuts. If rollback is required, restore a matching application and database state and verify integrity before reopening traffic.