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...

Docker Compose Environment Variable Not Set in Container: Fixes
You ran docker-compose up, but the environment variable you defined isn't availa...

Fix Docker Build Context Canceled on Windows 10
When building a Docker image on Windows 10, you may see an error like build context cancele...

How to Fix Nginx Redirect Loop with Cloudflare
You set up Cloudflare for your site, and now visitors see a redirect loop error. The page keeps r...

Fix 'git pull failed index.lock file exists' Error
When running git pull, you may see an error like:
fatal: Unable to create &#...

Python Virtual Environment Not Activating: Common Fixes
You run source venv/bin/activate (or venv\Scripts\activate on Windows) ...