Hi @danwetherald,
@pavel is correct that we run our own init as PID 1 which prevents systemd from running normally. However, we have had some internal success starting systemd in its own namespace using unshare:
CMD ["unshare", "--pid", "--fork", "--mount-proc", "/lib/systemd/systemd"]
Then you can use nsenter to enter the namespace to run systemctl commands.
There might be some rough edges, but hopefully this gives you a starting point for some further experimentation if you’re interested. Let me know if this works for you!