Docker OTOH composes whole services nicely: if my project needs a redis cache and postgres instance, I don't have to faff about with local ports, traefik can pick up my web server, and so on. I use a flake to create and lock a local development toolchain, but it's no help in managing the services.

One thing I haven't tried yet is building a container from a flake, which would have obvious benefits for reproducibility. Still don't think it would help with service orchestration though.