Checklists for software errors, setup, and tool workflows.

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Latest checklists

If you see fatal: unable to access 'https://...': SSL certificate problem: unable t...

Fix Git Authentication Failed in VS Code on Linux
You're working in VS Code on Linux, try to push or pull, and get a popup: "Git authentica...

Fix Python Venv Not Activating in PowerShell
You open PowerShell, navigate to your project, and run venv\Scripts\activate but not...

Python Requests Timeout Best Practices for Reliable Apps
When your Python script using the requests library hangs indefinitely on a slow or u...

Fix Node.js Heap Out of Memory Error in PM2
If you're running a Node.js application under PM2 and seeing FATAL ERROR: CALL_AND_RETR...

Fix Cloudflare Wildcard Subdomain Not Working
If you've set up a wildcard DNS record in Cloudflare (e.g., *.example.com) but s...