I’ve definitely made a post about Spiderfoot (See Technique, Tool and Lecture #3 HERE)
It’s the best of it’s kind, and although nothing replaces manual OSINT, Spiderfoot does cover A LOT of ground so you don’t have to.
Anyway, the creator recently posted a blog post about his journey from first creating Spiderfoot in C# (20 years ago!) before rewriting it in Python 10 years later.
Definitely check out the blog post HERE, it’s a great read for fans of the tool or people who maintain open source projects.
Also make sure you have Spiderfoot in the OSINT folder on your box!
Lastly, just want to thank Steve Micallef for his great work and y’all should go follow him on Twitter! @binarypool