Checklists for software errors, setup, and tool workflows.

Fix 'git pull failed index.lock file exists' Error

When running git pull, you may see an error like:

fatal: Unable to create &#...

Resolving Python Dependency Conflicts in pyproject.toml

You've updated a dependency in pyproject.toml, and now pip install ...

Fix Node Sass Build Failure After npm Cache Clean

If you've run npm cache clean --force and now see a build failure related to

Cloudflare DNS Not Propagating to All Nameservers: Common Fixes

You changed a DNS record in Cloudflare, but some resolvers still show the old value while others ...

Nginx Configuration Test Failed: Fix Server Block Errors

When you run nginx -t and see "test failed" with a server block error, it us...

Fix Nginx Upstream Connection Refused Socket Error

When Nginx returns a 502 Bad Gateway or logs upstream connection refused