FreeBSD on RISC-V
I didn’t know about this, despite being years in the making. The FreeBSD Wiki has more details:
As a result of this work, FreeBSD is able to boot to multi-user mode on the Spike simulator and QEMU emulator. Following a number of commits to the FreeBSD subversion repository in January 2016 (see riscv/history), FreeBSD is the first operating system to have bootable in-tree support for RISC-V.
Another advantage of having a self-contained operating system I guess.