I'm trying to get Docker installed on my compbio lab machines, which needs to have a rootless version of Docker due to user permissions in the lab. This might be a possible scenario for other people as well (wanting to run SPRAS but not having root access).

Our IT dept suggested MacOS + Podman, a command line tool that uses a library that doesn't depend on a daemon and doesn't require root privileges. It appears that you can run existing Docker images using Podman since they are compatible with the OCI standard (see, for example, this tutorial).

If this would be a useful thing to pursue, we can get Podman installed on our machines and test SPRAS. I imagine this might be similar to the singularity wrappers @agitter wrote, so it would potentially be a larger change (but the code structure seems amenable to it).