QEMU

QEMU is a free and open-source emulator. It emulates a computer’s processor through dynamic binary translation and provides a set of different hardware and device models for the machine, enabling it to run a variety of guest operating systems.

I’m pretty sure the guy from hamster.works was talking about how his startup was built on top of QEMU. Hemal Shah was also talking about this.

https://medium.com/@nullbyte.in/docker-and-qemu-a-powerful-combination-for-accelerating-edge-computing-development-and-optimizing-42da00259a02