oh yes they do nix very well, but I asked cursor to set up a firecracker vm with networking for exposing a port on the host, and use conda inside to install a certain version of python with some libraries. I asked for a firecracker-vm.nix, a build.sh, a run.sh and a close.sh. it kept trying to run code inside its own fhs-env, which would run, and then when I tried it outside of the fhs, it would fail. I'd paste in the errors and it would without fail say oh let's try the proper nix version of python - which I explicitly didn't want, because I wanted to run conda versions on other machines. I tried to guide it through conda-shell but didn't get very far. in the end I ended up using docker instead, which it did set up without fail.
but when it was failing on my original idea, it kept trying dumb things that weren't really even nix after a while.