Checklists for software errors, setup, and tool workflows.

1. Reproduce

2. Isolate

3. Apply

4. Verify

Latest checklists

If you see "npm run build" fail with a generic error message, you're not alone. The i...

You set up a wildcard DNS record (e.g., *.example.com) in Cloudflare, but new subdom...

When Nginx returns a 502 Bad Gateway or logs upstream connection refused

Nginx Redirect Loop: Common Causes and Fixes
You set up a redirect in nginx, but now your browser shows 'redirect loop' or 'too ma...

Fix Nginx Configuration Test Failure After Adding Proxy Pass
You add a proxy_pass directive to an Nginx server block, run nginx -t, ...

Fix Git Clone Connection Timed Out Due to Proxy Settings
You run git clone https://github.com/example/repo.git and after a long pause you get...