What is sqlite written in?

SQLite is so extensively tested and widely used it may as well be written in stone. It doesn't count as "writing C".

I think the parent is being a little tongue-in-cheek, but it’s a valid point. C is a dangerously inappropriate language to use... except when it isn’t.

C still has some unique portability characteristics that are very hard to match in other languages. If your requirements lead you down this path, it can be done.

You rightly point out however that this isn’t a path one travels lightly. Maybe the flip side of all this is, “if you’re prepared to invest the kind of rigor into testing that SQLite has, then rock on.”

Yeah, if you run into a security vulnerability caused by SQLite, tens of thousands of websites, desktop apps, and virtually every iOS and Android app will be in the exect same boat.

Or OpenBSD, for that matter.