I'm curious how you managed to find nothing on lcamtuf. He's one of the most famous Polish hackers from the 90s, then one the best security researchers Google had. Even if you live under a rock, the substack has an "about" section.
If it wasn't for Michał I'd probably be a farmer today.
Did you bother to google his handle? While I don't know his pure mathematics credentials, he's nerd-famous enough to not warrant an introduction. In fact, you not recognizing it says something about you.
To be fair, we are on hacker news. I did once use on of his programs, American Fuzzy Lopper (fake advertisement lawsuit incoming if its not american). So he is not nobody apparently