NixOS/modules/dev/rust.nix

{
  config,
  inputs,
  lib,
  pkgs,
  ...
}:
let
  packages = builtins.attrValues {
    inherit (pkgs)
      rustc # Rust compiler
      cargo # Rust package manager
      rust-analyzer # Language server for Rust
      clippy # Linter for Rust
      rustfmt # Formatter for Rust code
      ;
  };
in
{
  options = {
    my.dev.rust = {
      enable = lib.mkEnableOption "Install Rust tooling globally";
      users = lib.mkOption {
        type = inputs.self.lib.usersOptionType lib;
        default = config.my.toggleUsers.dev;
        description = "Users to install Rust packages for";
      };
    };
    devShells.rust = lib.mkOption {
      type = lib.types.package;
      default = pkgs.mkShell {
        inherit packages;
        name = "rust-dev-shell";
        shellHook = ''
          echo "🦀 Rust dev environment"
        '';
      };
      description = "Rust development shell with cargo and rust-analyzer";
    };
  };
  config = lib.mkMerge [
    (lib.mkIf config.my.dev.rust.enable {
      users.users = inputs.self.lib.mkUserAttrs lib config.my.dev.rust.users { inherit packages; };
    })
    {
      environment.variables.CARGO_HOME = "\${XDG_DATA_HOME}/cargo";
    }
  ];
}