In reply to @tomberek:matrix.org
The remote build system is powerful, but doing this and breaking out of the sandbox in a safe way will take some care. But yes, this can be done; I used this as a quick data transformation engine orchestrated by Hydra, you just gotta be careful and ensure you end up with the properties you want.

In reply to @flyx:klacker.eu
can I use Nix Flakes purely as a solution for remote compiling? like, my (otherwise Nix-less) project requires me to build it on a remote machine and I have some hacky rsync-up---compile---rsync-down script which I want to replace with something more sensible, and Nix provides remote building capabilities. so if I write an impure Flake that just calls the system compiler and doesn’t use any Nix features, would this be a feasible solution for remote compiling?

    runBuildOnLinux = pkgs.writeShellApplication {
      name = "run-build-on-linux";
      runtimeInputs = [pkgs.jq];
      text = ''
        target="$1"; shift
        copy_result_back="''${2:-true}"
        flake=$(nix flake metadata --json | jq -r .path)
        if [ "$(uname -s)" = "Linux" ]; then
            # nothing to do, we're on linux already
            exec nix build --json --no-link "$@" -L "$flake#$target" | jq -r '.[0].outputs.out'
            exit 0
        fi

        remote_machine="''${REMOTE_MACHINE:-gloria.home}"
        nix copy --to "ssh-ng://$remote_machine" "$flake"
        out="$(ssh "$remote_machine" nix build --json --no-link -L "$@" "$flake#$target" | jq -r '.[0].outputs.out')"
        if [ "$copy_result_back" = "true" ]; then
            nix copy --no-check-sigs --from "ssh-ng://$remote_machine" "$out"
        fi
        echo "$out"
      '';
    };

is that script

In reply to @flyx:klacker.eu
can I use Nix Flakes purely as a solution for remote compiling? like, my (otherwise Nix-less) project requires me to build it on a remote machine and I have some hacky rsync-up---compile---rsync-down script which I want to replace with something more sensible, and Nix provides remote building capabilities. so if I write an impure Flake that just calls the system compiler and doesn’t use any Nix features, would this be a feasible solution for remote compiling?