Checklists for software errors, setup, and tool workflows.

1. Reproduce

2. Isolate

3. Apply

4. Verify

Latest checklists

You're working on a Python project managed by Poetry, and after adding or updating a dependen...

If you see a 'Secure Connection Failed' error in Firefox that mentions date or time, it u...

If you're seeing fatal: unable to access 'https://...' : Failed to connect ...:...

Fix Blue Screen Loop After Windows 11 Update
You install a Windows 11 update, restart, and then get stuck in a blue screen loop—the system cra...

Python Virtual Environment Not Activating on Mac: Fixes
You open Terminal, run source venv/bin/activate, and nothing happens—or you get an e...

Fix Nginx 'upstream connection refused' When Talking to PHP-FPM
You're seeing upstream connection refused in your Nginx error log, and your site...