{
  inputs = {
    nixpkgs.url = "github:nixos/nixpkgs?ref=nixos-unstable";

    rust-overlay.url = "github:oxalica/rust-overlay";
    rust-overlay.inputs.nixpkgs.follows = "nixpkgs";
  };

  outputs = { self, nixpkgs, rust-overlay }: let
    systems = [
      "x86_64-linux"
      "x86_64-darwin"
      "aarch64-linux"
      "aarch64-darwin"
      "armv7l-linux"
    ];

    forAllSystems = f: nixpkgs.lib.genAttrs systems (system: let
      pkgs = import nixpkgs {
        inherit system;
        overlays = [
          (import rust-overlay)
        ];
      };

    in f system pkgs);

    inherit (nixpkgs) lib;
  in {
    devShells = forAllSystems (system: pkgs: {
      rust = pkgs.callPackage ./generic/rust/shell.nix { };
      rust-nightly = pkgs.callPackage ./generic/rust/shell.nix { rust-channel = "nightly"; };

      github-MusicPlayerDaemon-MPD = pkgs.callPackage ./projects/github/MusicPlayerDaemon/MPD/shell.nix { };
    });
  };
}