Here’s their pitch:

Do you have a home server you want to run a few apps on, but don’t want everything to
break every time you upgrade the OS? Do you want automatic updates but don’t want to buy
an extra 4 servers so you can run Kubernetes?

Do you have a work server that you want to run a few small services on, but don’t want
to have to manually manage it? Do you find that having every deployment action be in
a git repo more tidy?

Harbormaster is for you.

You create a YAML config file with all the git repos you want it to include and it’ll watch them for changes (on a timer) and do the necessary cloning/pulling, service restarting, etc. that needs doing to make it all run. Simple. Neat!