Checklists for software errors, setup, and tool workflows.

1. Reproduce

2. Isolate

3. Apply

4. Verify

Latest checklists

If you see fatal: unable to access 'https://...': SSL certificate problem: unable t...

Fix npm ENOENT package.json Not Found Due to Wrong Directory
You run npm install or npm start and get an error like ENOENT: no...

Fix npm install Permission Denied When Using nvm
If you see 'EACCES: permission denied' when running npm install while using ...

How to Fix the Git index.lock File Exists Error
You're in the middle of a Git operation—commit, merge, or rebase—and Git stops with: fa...

Fix Nginx 502 Bad Gateway on Docker Ubuntu
You're running Nginx as a reverse proxy inside Docker on Ubuntu, and suddenly you see

Nginx Redirect Loop Not Working: Causes and Fixes
You've set up a redirect in Nginx, but instead of landing on the intended URL, the browser sh...