Checklists for software errors, setup, and tool workflows.

1. Reproduce

2. Isolate

3. Apply

4. Verify

Latest checklists

You try to run a Git command and see fatal: Unable to create 'path/.git/index.lock'...

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 pnpm ERR! Cannot Find Module – Practical Steps
When running pnpm install or pnpm start, you might see an error like:

How to Resolve Permission Denied Errors with pip install
If you see PermissionError: [Errno 13] Permission denied while running pip ins...

Fix pip Error: Externally Managed Environment
If you're on a modern Linux distribution (like Debian 12, Ubuntu 23.04+, Fedora, or Arch) and...

Fix npm run build Failed Due to Webpack Configuration
When npm run build fails, the error often points to a webpack configuration issue. T...