diff --git a/nixpkgs.nix b/nixpkgs.nix
new file mode 100644
index 0000000..219a3cf
--- /dev/null
+++ b/nixpkgs.nix
@@ -0,0 +1,6 @@
+import (
+  builtins.fetchTarball {
+    url = "https://github.com/nixos/nixpkgs/archive/a7bf8161fa834a602278c15fcbdd955656b3aed8.tar.gz";
+    sha256 = "0lzd35niw0j8qy4mhglvqwv5qwyvdb9mhv8hpmn73ym57r92i4p1";
+  }
+)
diff --git a/shell.nix b/shell.nix
index cb227f2..94152f6 100644
--- a/shell.nix
+++ b/shell.nix
@@ -1,9 +1,17 @@
 let
-  pkgs = import <nixpkgs> {};
-
-  default = import ./default.nix {};
+  pkgs = import ./nixpkgs.nix {};
+  default = import ./default.nix { inherit pkgs; };
 
 in
-pkgs.mkShell {
-  buildInputs = builtins.attrValues default;
-}
+  with default;
+  pkgs.mkShell {
+    buildInputs = [
+      dhall-simple
+      dhall-json-simple
+      dhall-bash-simple
+    ] ++ (
+      if pkgs.stdenv.isDarwin then [] else [
+        dhall-nix-simple
+      ]
+    );
+  }
diff --git a/test.bash b/test.bash
index c65802b..e6c8191 100755
--- a/test.bash
+++ b/test.bash
@@ -17,6 +17,10 @@ function test_exe () {
 test_exe dhall;
 test_exe dhall-to-json;
 test_exe dhall-to-bash;
-test_exe dhall-to-nix;
+
+if [[ "$OSTYPE" != "darwin"* ]]
+then
+  test_exe dhall-to-nix;
+fi
 
 exit $ERRORS;