Checklists for software errors, setup, and tool workflows.

1. Reproduce

2. Isolate

3. Apply

4. Verify

Latest checklists

When running Python in Git Bash on Windows, you may see bash: python: command not found

Fix Cloudflare Wildcard Subdomain Not Working
If you've set up a wildcard DNS record in Cloudflare (e.g., *.example.com) but s...

Fix ERR_CERT_AUTHORITY_INVALID in Chrome Incognito Mode
You open Chrome incognito and hit a warning: NET::ERR_CERT_AUTHORITY_INVALID. Th...

How to Create a package.json for Your npm Project
If you're starting a Node.js project, you'll need a package.json file. This ...

Fix Git Clone Connection Timed Out via HTTPS
When cloning a repository over HTTPS, you may see 'Connection timed out' after a long wai...

Fix Nginx Upstream Connection Refused Timeout Error
When Nginx returns 502 Bad Gateway or logs upstream connection refused timeout...