I always thought it could be cool to use systemd as a CI agent replacement someday: Each systemd service could represent a step built by running a script, and

I always thought it could be cool to use systemd as a CI agent replacement someday: Each systemd service could represent a step built by running a script, and each service can say what it depends on, thus helping parallelize any step that can be. I have not found anyone trying that so far. Is anybody aware of something similar and more POSIX/cross platform that allows writing a DAG of scripts to execute?