Checklists for software errors, setup, and tool workflows.

1. Reproduce

2. Isolate

3. Apply

4. Verify

Latest checklists

You're running Nginx as a reverse proxy inside Docker on Ubuntu, and suddenly you see

When Nginx returns 502 Bad Gateway or logs upstream connection refused timeout...

Fix VSCode Breakpoints Not Hit in launch.json
You set a breakpoint in Visual Studio Code, start debugging with a launch.json confi...

Cloudflare SSL Full Strict Setup Guide
If you enable Cloudflare's SSL/TLS encryption and set it to Full (Strict), y...

How to Fix Git Index Lock File Exists Error
If you see an error like fatal: Unable to create 'path/to/repo/.git/index.lock': Fi...

How to Fix Git Merge Conflict Permission Denied Errors
You're in the middle of a git merge, and instead of the usual conflict markers, you see