Checklists for software errors, setup, and tool workflows.

How to Fix Nginx 'Upstream Connection Refused' Error

When Nginx returns a 502 Bad Gateway with upstream connection refused in the error l...

How to Merge a Git Detached HEAD Back to Master

If you see a message like 'You are in 'detached HEAD' state' after checking out a...

Fix VS Code Source Control Not Detecting File Modifications

You edit a file, save it, but the Source Control panel in VS Code shows nothing. No pending chang...

Fix npm install Permission Denied on Linux

When you run npm install on Linux and hit a permission denied error, it usually mean...

Fix Docker Container Exits Immediately in Background Mode

You run a Docker container with -d (detached mode) and it exits immediately. The con...

Fix Git SSL Certificate Error: Unable to Get Local Issuer Certificate

When cloning or pulling from a Git repository, you may see:

fatal: unable to access...