Checklists for software errors, setup, and tool workflows.

Fix Cloudflare Origin Certificate Mismatch Errors

If you see 'Origin Certificate Mismatch' in Cloudflare or browser warnings, it usually me...

Git Merge Conflict: How to See the Diff Between Versions

When you run git merge and hit a conflict, Git pauses and marks the conflicting file...

Fix 'package.json Not Found' After Cloning a Repository

Symptom

You clone a repository from GitHub (or another remote), change into the directory...

How to Fix Git Detached HEAD State and Undo Changes

You run git status and see something like "HEAD detached at abc123". This ha...

Fix npm install Permission Denied (EACCES) Error

When you run npm install and see an error like Error: EACCES: permission denie...