Checklists for software errors, setup, and tool workflows.

1. Reproduce

2. Isolate

3. Apply

4. Verify

Latest checklists

You try to push a commit to a remote repository and get: ! [rejected] main -> main (non-...

Git index.lock File Exists Even After Deleting: Fixes
You delete the .git/index.lock file, but Git still says it exists. This can happen d...

Fix Nginx Upstream Connection Refused Socket Error
When Nginx returns a 502 Bad Gateway or logs upstream connection refused

Fix Docker 'No Space Left on Device' Volume Error
When Docker reports 'no space left on device' for a volume, the symptom is often a contai...

VSCode Integrated Terminal Not Showing: Fixes to Try
You open the integrated terminal in Visual Studio Code using Ctrl+` (or Cmd+`<...

Fixing Nginx Upstream Connection Refused in Load Balancing
When Nginx load balancing returns upstream connection refused, it means one or more ...