Checklists for software errors, setup, and tool workflows.

1. Reproduce

2. Isolate

3. Apply

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Latest checklists

You run git push and see: ! [rejected] main -> main (non-fast-forward)

Fix Nginx 502 Bad Gateway with Docker Environment Variables
If you see a 502 Bad Gateway from nginx running in Docker, it usually means ngin...

Fix VS Code Git Authentication Failure with No Prompt
You try to push or pull in VS Code and see an error like "Git authentication failed" but ...

Fix Git 'index.lock' File Exists Error on Linux
When working with Git on Linux, you might see an error like:
fatal: Unable to creat...

Fix 'pip install externally managed environment' Error
If you're seeing pip install fail with a message about an externally managed env...

Fix Nginx Upstream Connection Refused Error
When Nginx returns upstream connection refused in your error logs, it means Nginx tr...