diff --git a/flake.nix b/flake.nix
index 2ac174e..508bfac 100644
--- a/flake.nix
+++ b/flake.nix
@@ -89,6 +89,9 @@
       inherit lib username;
     };
 
+    nixosModules = import ./modules/nixos;
+    homeManagerModules = import ./modules/home-manager;
+
     nixosConfigurations = {
       slab = lib.nixosSystem rec {
         system = "x86_64-linux";
diff --git a/modules/home-manager/default.nix b/modules/home-manager/default.nix
new file mode 100644
index 0000000..0967ef4
--- /dev/null
+++ b/modules/home-manager/default.nix
@@ -0,0 +1 @@
+{}
diff --git a/modules/nixos/adb-old.nix b/modules/nixos/adb-old.nix
new file mode 100644
index 0000000..691508e
--- /dev/null
+++ b/modules/nixos/adb-old.nix
@@ -0,0 +1,29 @@
+{ config, lib, pkgs, extraPkgs, ... }:
+
+with lib;
+
+{
+  meta.maintainers = [ maintainers.mic92 ];
+
+  ###### interface
+  options = {
+    programs.adb = {
+      enable = mkOption {
+        default = false;
+        type = types.bool;
+        description = lib.mdDoc ''
+          Whether to configure system to use Android Debug Bridge (adb).
+          To grant access to a user, it must be part of adbusers group:
+          `users.users.alice.extraGroups = ["adbusers"];`
+        '';
+      };
+    };
+  };
+
+  ###### implementation
+  config = mkIf config.programs.adb.enable {
+    services.udev.packages = [ extraPkgs.android-udev-rules ];
+    environment.systemPackages = [ extraPkgs.android-tools ];
+    users.groups.adbusers = {};
+  };
+}
diff --git a/modules/nixos/default.nix b/modules/nixos/default.nix
new file mode 100644
index 0000000..d227158
--- /dev/null
+++ b/modules/nixos/default.nix
@@ -0,0 +1,3 @@
+{
+  adb = import ./adb-old.nix;
+}