Unfortunately I'm not at liberty to dive deep into those details. I will say that Firecracker can be used on bare metal EC2 instances, whether you're a public customer or AWS itself. :-)

I guess I should have peeked at the source code when I was there…

No need, at least when I was there when the day was still one, before the pandemic. And well, Firecracker is open source.

A few of the best technical presentations that I've watched were at a pre-SKO event. Nitro, Graviton and Firecracker.

Great engineering pieces, the three of them.