Checklists for software errors, setup, and tool workflows.

1. Reproduce

2. Isolate

3. Apply

4. Verify

Latest checklists

If Firefox shows 'Secure Connection Failed' on every website you try to visit, it usually...

When you run docker pull for a private repository and get an access denied

Fix 'Externally Managed Environment' Error on Linux
If you're on a modern Linux distribution (Ubuntu 23.04+, Debian 12+, Fedora 38+, etc.) and ge...

Checklist for Pushing Large Files with Git
You've likely hit this: you try to push a commit, and Git rejects it because a file is too la...

Python Virtual Environment Not Activating: Common Fixes
You run source venv/bin/activate (or venv\Scripts\activate on Windows) ...

Fix Nginx Upstream Connection Refused in Proxy Pass
When Nginx returns a 502 Bad Gateway or logs upstream connection refused