Note the instructions use podman instead of docker because at time of writing, docker doesn't yet have support for cgroup2.

Prebuilt image

$ podman run --privileged --cgroupns=host --pid=host -it below/below:latest

Local build

$ git clone https://github.com/facebookincubator/below.git ~/dev/below
<...>

$ cd ~/dev/below

$ podman build -t below .
<...>

$ podman run --privileged --cgroupns=host --pid=host -it below