Checklists for software errors, setup, and tool workflows.

1. Reproduce

2. Isolate

3. Apply

4. Verify

Latest checklists

You try to merge two Git branches and get this error:

fatal: refusing to merge unre...

Fix ERR_CERT_AUTHORITY_INVALID on Localhost
When testing a local web app, you may see ERR_CERT_AUTHORITY_INVALID in Chrome or si...

Fix Cloudflare 521 Error: DNS Configuration Problem
If you see a Cloudflare 521 error page, it means Cloudflare's servers are unable to connect t...

Cloudflare DNS Setup Propagation Not Completing: Fixes
You've updated your DNS records at Cloudflare, but hours later the changes still aren't s...

Fix pnpm ERR_PNPM_OUTDATED_LOCKFILE Lockfile Error
When running pnpm install or pnpm update, you may see:
ER...

Fix npm run build Failed Due to Webpack Configuration
When npm run build fails, the error often points to a webpack configuration issue. T...