diff --git a/modules/environment/login/login-inner.nix b/modules/environment/login/login-inner.nix
index 6e05cfa..2440a73 100644
--- a/modules/environment/login/login-inner.nix
+++ b/modules/environment/login/login-inner.nix
@@ -9,7 +9,7 @@ in
 writeText "login-inner" ''
   # This file is generated by nix-on-droid. DO NOT EDIT.
 
-  set -eu -o pipefail
+  set -eo pipefail
 
   if [ "$#" -eq 0 ]; then  # if script is called from within nix-on-droid app
     echo "Welcome to Nix-on-Droid!"
diff --git a/modules/environment/shell.nix b/modules/environment/shell.nix
new file mode 100644
index 0000000..d79c95c
--- /dev/null
+++ b/modules/environment/shell.nix
@@ -0,0 +1,32 @@
+# Copyright (c) 2019-2021, see AUTHORS. Licensed under MIT License, see LICENSE.
+
+{ config, lib, pkgs, ... }:
+
+with lib;
+
+{
+
+  ###### interface
+
+  options = {
+
+  };
+
+
+  ###### implementation
+
+  config = {
+
+    environment.etc = {
+      "profile".text = ''
+        . "${config.build.sessionInit}/etc/profile.d/nix-on-droid-session-init.sh"
+      '';
+
+      "zshenv".text = ''
+        . "${config.build.sessionInit}/etc/profile.d/nix-on-droid-session-init.sh"
+      '';
+    };
+
+  };
+
+}
diff --git a/modules/module-list.nix b/modules/module-list.nix
index 768ad0a..bbd4269 100644
--- a/modules/module-list.nix
+++ b/modules/module-list.nix
@@ -13,6 +13,7 @@
   ./environment/nix.nix
   ./environment/path.nix
   ./environment/session-init.nix
+  ./environment/shell.nix
   ./home-manager.nix
   ./nixpkgs/options.nix
   ./time.nix