Checklists for software errors, setup, and tool workflows.

1. Reproduce

2. Isolate

3. Apply

4. Verify

Latest checklists

When running pnpm install or pnpm start, you might see an error like:

If you've ever tried to load a CSV file that's several gigabytes into pandas with p...

Fix Nginx Upstream Connection Refused Socket Error
When Nginx returns a 502 Bad Gateway or logs upstream connection refused

Checklist for Nginx Configuration Test Failure
When you run nginx -t and get a failure, the server won't reload or restart. Thi...

Fix Nginx 502 Bad Gateway with Docker and PHP-FPM
You have a Docker setup with Nginx proxying to a PHP-FPM container, and you're getting a 502 ...

How to Fix Cloudflare 522 Errors: Connection Timeout Guide
You're trying to load your site and see Error 522: Connection Timed Out. Thi...