Checklists for software errors, setup, and tool workflows.

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3. Apply

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Latest checklists

You run docker compose up and get an error like Error: Port 3306 is already al...

How to Fix Git Detached HEAD State and Undo Changes
You run git status and see something like "HEAD detached at abc123". This ha...

How to Update Node Version for Package Compatibility
When you run npm install and see warnings about engine incompatibility or errors lik...

Git Fatal: Refusing to Merge Unrelated Histories – Workaround
You try to merge two Git branches and get this error:
fatal: refusing to merge unre...

Fix Nginx Redirect Loop After SSL Setup
You've set up SSL on your Nginx server, but now visitors get stuck in a redirect loop—HTTP→HT...

Fix 'port already allocated' for Nginx in Docker Compose
You're starting your Docker Compose setup with Nginx, and you see "port is already alloca...