nicoburns parent
What I really want is a tool like docker compose that builds on top of a tool like this (instead of docker)
Assuming you want the service management aspect of docker compose look at user-mode process supervisors like supervisord. You can install it in your nix environment and config all the dependent services it should manage. It's a little more crufty vs. the simplicity of docker compose but it also has a lot more power and flexibility. There are tons of other options to explore too like systemd user services or skarnet's s6 suite.