Oh neat! I made something a while back that scratched my itch for this exact problem: https://github.com/christiangenco/autorunner

I chose to build the commands into the file with a comment rather than add an extra config file. For your test-compile cycle for Go, I think that would look like this at the top of each of your go files:

# autorun go install ./cmd/devd

modd looks like it has the advantage of only specifying this one, and specifying commands to be run when modd first starts up (autorun only has one type of command that's run on startup and on file changes).