Although he's done a lot of great work those aren't maintained now and they're a bit of kludge in my experience. Mr. Chromebox maintains a coreboot firmware[1] that is really good, and the maintainer is active on r/chromeos.

Chromebook hardware is pretty damn good for running linux, I've had zero problems with this firmware and xubuntu. Everything just works now for the most part.

[1] https://mrchromebox.tech/