Checklists for software errors, setup, and tool workflows.

1. Reproduce

2. Isolate

3. Apply

4. Verify

Latest checklists

If you see the error error: externally-managed-environment when running pip in...

Fix npm run build Failure from Missing Env Variables
You run npm run build and get an error like Error: Missing required environmen...

Fix Nginx 'Permission Denied' Upstream Errors
When Nginx logs permission denied while connecting to an upstream (e.g., a Unix sock...

Git Push Rejected Non Fast Forward: How to Fix
You run git push and see: ! [rejected] main -> main (non-fast-forward)

How to Push a Git Detached HEAD to Remote
You're working on a Git repository and realize you're in a 'detached HEAD' state....

Cloudflare Origin Certificate Setup Checklist
If you're setting up a Cloudflare origin certificate to encrypt traffic between Cloudflare an...