Checklists for software errors, setup, and tool workflows.

1. Reproduce

2. Isolate

3. Apply

4. Verify

Latest checklists

When you see net::ERR_CERT_AUTHORITY_INVALID in Chrome on Linux, it usually means th...

You notice the Windows Security icon in the system tray shows a yellow warning. Opening it reveal...

When you see npm ERR! enoent ENOENT: no such file or directory, open '.../package.json&...

Fixing NGINX Upstream Connection Refused SSL Errors
When NGINX logs upstream connection refused for an SSL backend, it usually means the...

Fix Git Push Rejected Due to Unrelated Histories
You try to push a local branch to a remote repository, but Git refuses with a message like ...

Python Requests Timeout Not Waiting: Fixes and Checks
You set a timeout in Python's requests library, but the call either hangs foreve...