FreeBSD on Firecracker

In June 2022, I started work on porting FreeBSD to run on Firecracker. My interest was driven by a few factors.

First, I had been doing a lot of work on speeding up the FreeBSD boot process and wanted to know the limits that could be reached with a minimal hypervisor.

Second, porting FreeBSD to new platforms always helps to reveal bugs - both in FreeBSD and on those platforms.

Third, AWS Lambda only supports Linux at present; I'm always eager to make FreeBSD more available in AWS (although adoption in Lambda is out of my control, Firecracker support would be a necessary precondition).

The largest reason, however, was simply because it's there. Firecracker is an interesting platform, and I wanted to see if I could make it work.

Firecracker is Amazon's virtual machine monitor. This article goes in great detail about the process of porting FreeBSD to run on Firecracker.