diff --git a/nixos/modules/services/monitoring/heapster.nix b/nixos/modules/services/monitoring/heapster.nix
index b8ba3632caca..ea03ec46c55c 100644
--- a/nixos/modules/services/monitoring/heapster.nix
+++ b/nixos/modules/services/monitoring/heapster.nix
@@ -1,35 +1,32 @@
 { config, lib, pkgs, ... }:
-
-with lib;
-
 let
   cfg = config.services.heapster;
 in {
   options.services.heapster = {
-    enable = mkEnableOption "Heapster monitoring";
+    enable = lib.mkEnableOption "Heapster monitoring";
 
-    source = mkOption {
+    source = lib.mkOption {
       description = "Heapster metric source";
       example = "kubernetes:https://kubernetes.default";
-      type = types.str;
+      type = lib.types.str;
     };
 
-    sink = mkOption {
+    sink = lib.mkOption {
       description = "Heapster metic sink";
       example = "influxdb:http://localhost:8086";
-      type = types.str;
+      type = lib.types.str;
     };
 
-    extraOpts = mkOption {
+    extraOpts = lib.mkOption {
       description = "Heapster extra options";
       default = "";
-      type = types.separatedString " ";
+      type = lib.types.separatedString " ";
     };
 
-    package = mkPackageOption pkgs "heapster" { };
+    package = lib.mkPackageOption pkgs "heapster" { };
   };
 
-  config = mkIf cfg.enable {
+  config = lib.mkIf cfg.enable {
     systemd.services.heapster = {
       wantedBy = ["multi-user.target"];
       after = ["cadvisor.service" "kube-apiserver.service"];