That's an Excellent point of view. I've noticed Docker does offer a full package of services and tooling to help keep processes isolated and easy to create. I'll for sure go into more detail in a second part. However, to answer your question, docker-compose is built separately from Docker and would be hard to replace with NixOS alone. That is only one example. NixOS does support Overlays which are useful but when compared to docker-compose you will get an easy experience.