from Hacker News

Made a configuration and guide to configure and use 3 clouds's DNS services to see where clouds such as GCP, Azure, and AWS think some computer is if some DNS names are dig'd up. I've already deployed this so it's already usable.

To be honest, I doubt this is useful for anything beyond curiosity and remediation if you see any issues is likely impossible. Kind of sadly useless I suppose.

Anyway, you don't need any tools on your computer except dig to resolve some CNAMEs. The readme is a guide.