diff --git a/default.nix b/default.nix
index d4d964a..7ee7c59 100644
--- a/default.nix
+++ b/default.nix
@@ -10,6 +10,8 @@ let
     inherit kubenix;
   };
 
+  # evalModules with same interface as lib.evalModules and kubenix as
+  # special argument
   evalModules = {
     module ? null,
     modules ? [module],
@@ -27,8 +29,9 @@ let
   modules = import ./modules;
 
   kubenix = {
-    inherit evalModules kubenix;
+    inherit evalModules modules;
 
     lib = kubenixLib;
-  } // modules;
+    module = modules.module;
+  };
 in kubenix
diff --git a/lib/default.nix b/lib/default.nix
index 266b6ed..257e02c 100644
--- a/lib/default.nix
+++ b/lib/default.nix
@@ -3,4 +3,5 @@
 (import ./extra.nix { inherit pkgs lib; }) // {
   k8s = import ./k8s.nix { inherit lib; };
   docker = import ./docker.nix { inherit lib pkgs; };
+  helm = import ./helm { inherit pkgs; };
 }
diff --git a/modules/helm/chart2json.nix b/lib/helm/chart2json.nix
similarity index 100%
rename from modules/helm/chart2json.nix
rename to lib/helm/chart2json.nix
diff --git a/lib/helm/default.nix b/lib/helm/default.nix
new file mode 100644
index 0000000..093251b
--- /dev/null
+++ b/lib/helm/default.nix
@@ -0,0 +1,6 @@
+{ pkgs }:
+
+{
+  chart2json = pkgs.callPackage ./chart2json.nix { };
+  fetch = pkgs.callPackage ./fetchhelm.nix { };
+}
diff --git a/modules/helm/fetchhelm.nix b/lib/helm/fetchhelm.nix
similarity index 100%
rename from modules/helm/fetchhelm.nix
rename to lib/helm/fetchhelm.nix
diff --git a/modules/helm/test.nix b/lib/helm/test.nix
similarity index 100%
rename from modules/helm/test.nix
rename to lib/helm/test.nix
diff --git a/modules/default.nix b/modules/default.nix
index 39b54b7..25678e6 100644
--- a/modules/default.nix
+++ b/modules/default.nix
@@ -1,9 +1,10 @@
 {
+  k8s = ./k8s.nix;
+  istio = ./istio.nix;
   submodules = ./submodules.nix;
-  k8s = ./k8s;
-  istio = ./istio;
-  testing = ./testing;
-  helm = ./helm;
-  docker = ./docker;
+  helm = ./helm.nix;
+  docker = ./docker.nix;
+  testing = ./testing.nix;
+  test = ./test.nix;
   module = ./module.nix;
 }
diff --git a/modules/docker/default.nix b/modules/docker.nix
similarity index 100%
rename from modules/docker/default.nix
rename to modules/docker.nix
diff --git a/modules/k8s/generated/v1.10.nix b/modules/generated/v1.10.nix
similarity index 100%
rename from modules/k8s/generated/v1.10.nix
rename to modules/generated/v1.10.nix
diff --git a/modules/k8s/generated/v1.11.nix b/modules/generated/v1.11.nix
similarity index 100%
rename from modules/k8s/generated/v1.11.nix
rename to modules/generated/v1.11.nix
diff --git a/modules/k8s/generated/v1.12.nix b/modules/generated/v1.12.nix
similarity index 100%
rename from modules/k8s/generated/v1.12.nix
rename to modules/generated/v1.12.nix
diff --git a/modules/k8s/generated/v1.13.nix b/modules/generated/v1.13.nix
similarity index 100%
rename from modules/k8s/generated/v1.13.nix
rename to modules/generated/v1.13.nix
diff --git a/modules/k8s/generated/v1.7.nix b/modules/generated/v1.7.nix
similarity index 100%
rename from modules/k8s/generated/v1.7.nix
rename to modules/generated/v1.7.nix
diff --git a/modules/k8s/generated/v1.8.nix b/modules/generated/v1.8.nix
similarity index 100%
rename from modules/k8s/generated/v1.8.nix
rename to modules/generated/v1.8.nix
diff --git a/modules/k8s/generated/v1.9.nix b/modules/generated/v1.9.nix
similarity index 100%
rename from modules/k8s/generated/v1.9.nix
rename to modules/generated/v1.9.nix
diff --git a/modules/helm/default.nix b/modules/helm.nix
similarity index 88%
rename from modules/helm/default.nix
rename to modules/helm.nix
index 065272c..b280efe 100644
--- a/modules/helm/default.nix
+++ b/modules/helm.nix
@@ -1,4 +1,7 @@
-{ config, lib, pkgs, kubenix, ... }:
+# helm defines kubenix module with options for using helm charts
+# with kubenix
+
+{ config, lib, pkgs, helm, ... }:
 
 with lib;
 
@@ -21,13 +24,11 @@ let
     version = last splitted;
   };
 
-  chart2json = pkgs.callPackage ./chart2json.nix {  };
-  fetchhelm = pkgs.callPackage ./fetchhelm.nix {  };
-
 in {
-  imports = [
-    kubenix.k8s
-  ];
+  imports = [ ./k8s.nix ];
+
+  # expose helm helper methods as module argument
+  config._module.args.helm = import ../lib/helm { inherit pkgs; };
 
   options.kubernetes.helm = {
     instances = mkOption {
@@ -86,19 +87,13 @@ in {
           metadata.namespace = mkDefault config.namespace;
         }];
 
-        config.objects = importJSON (chart2json {
+        config.objects = importJSON (helm.chart2json {
           inherit (config) chart name namespace values kubeVersion;
         });
       }));
     };
   };
 
-  # include helper helm methods as args
-  config._module.args.helm = {
-    fetch = fetchhelm;
-    chart2json = chart2json;
-  };
-
   config.kubernetes.api = mkMerge (flatten (mapAttrsToList (_: instance:
     map (object: let
       apiVersion = parseApiVersion object.apiVersion;
diff --git a/modules/istio/overrides.nix b/modules/istio-overrides.nix
similarity index 100%
rename from modules/istio/overrides.nix
rename to modules/istio-overrides.nix
diff --git a/modules/istio/default.nix b/modules/istio.nix
similarity index 99%
rename from modules/istio/default.nix
rename to modules/istio.nix
index 51c4f9f..b019440 100644
--- a/modules/istio/default.nix
+++ b/modules/istio.nix
@@ -4697,7 +4697,7 @@ let
       };
     };
 
-  } // (import ./overrides.nix {inherit definitions lib;});
+  } // (import ./istio-overrides.nix {inherit definitions lib;});
 in {
   kubernetes.customResources = [
   {
diff --git a/modules/k8s/default.nix b/modules/k8s.nix
similarity index 97%
rename from modules/k8s/default.nix
rename to modules/k8s.nix
index 49a0070..22b2035 100644
--- a/modules/k8s/default.nix
+++ b/modules/k8s.nix
@@ -1,3 +1,5 @@
+# K8S module defines kubernetes definitions for kubenix
+
 { config, lib, pkgs, k8s, ... }:
 
 with lib;
@@ -108,8 +110,8 @@ let
   indexOf = lst: value:
     head (filter (v: v != -1) (imap0 (i: v: if v == value then i else -1) lst));
 in {
-  # expose k8s helper methods through arg in modules
-  config._module.args.k8s = import ../../lib/k8s.nix { inherit lib; };
+  # expose k8s helper methods as module argument
+  config._module.args.k8s = import ../lib/k8s.nix { inherit lib; };
 
   options.kubernetes.version = mkOption {
     description = "Kubernetes version to use";
diff --git a/modules/k8s/submodule.nix b/modules/k8s/submodule.nix
deleted file mode 100644
index fe9fc58..0000000
--- a/modules/k8s/submodule.nix
+++ /dev/null
@@ -1,59 +0,0 @@
-{ config, lib, kubenix, ... }:
-
-with lib;
-
-let
-  globalConfig = config;
-in {
-  imports = [ kubenix.submodules ];
-
-  options = {
-    kubernetes.propagateDefaults = mkOption {
-      description = "Whether to propagate child defaults to submodules";
-      type = types.bool;
-      default = true;
-    };
-
-    submodules.instances = mkOption {
-       type = types.attrsOf (types.submodule ({config, ...}: {
-        options = {
-          namespace = mkOption {
-            description = "Default kubernetes namespace";
-            type = types.str;
-            default = "default";
-          };
-        };
-
-        config.config = {
-          kubernetes.api.defaults = [{
-            default.metadata.namespace = mkDefault config.namespace;
-          }];
-        };
-      }));
-    };
-  };
-
-  config = {
-    submodules.defaults = [{
-      default = {
-        imports = [ kubenix.k8s ];
-        kubernetes.version = mkDefault config.kubernetes.version;
-        kubernetes.api.defaults =
-          mkIf config.kubernetes.propagateDefaults config.kubernetes.api.defaults;
-      };
-    } {
-      default = ({config, ...}: {
-        kubernetes.api.defaults = [{
-          default.metadata.labels = {
-            "kubenix/module-name" = config.submodule.name;
-            "kubenix/module-version" = config.submodule.version;
-          };
-        }];
-      });
-    }];
-
-    kubernetes.objects = mkMerge (mapAttrsToList (_: submodule:
-      submodule.config.kubernetes.objects
-    ) config.submodules.instances);
-  };
-}
diff --git a/modules/module.nix b/modules/module.nix
index ea2747c..33a2e47 100644
--- a/modules/module.nix
+++ b/modules/module.nix
@@ -1,11 +1,15 @@
-{ config, lib, kubenix, ... }:
+# module.nix defines default kubenix module with additional helper options
+# and preincluded kubenix module definitions for kubernetes, docker and
+# kubenix submodules
+
+{ config, lib, ... }:
 
 with lib;
 
 let
   parentConfig = config;
 in {
-  imports = with kubenix; [ submodules k8s docker ];
+  imports = [ ./k8s.nix ./docker.nix ./submodules.nix ];
 
   options = {
     kubenix.release = mkOption {
@@ -42,7 +46,7 @@ in {
   config = {
     submodules.defaults = [{
       default = {
-        imports = [ kubenix.module ];
+        imports = [ ./module.nix ];
         kubernetes.version = mkDefault config.kubernetes.version;
         kubernetes.api.defaults =
           mkIf config.kubernetes.propagateDefaults config.kubernetes.api.defaults;
diff --git a/modules/testing/test.nix b/modules/test.nix
similarity index 100%
rename from modules/testing/test.nix
rename to modules/test.nix
diff --git a/modules/testing/default.nix b/modules/testing.nix
similarity index 100%
rename from modules/testing/default.nix
rename to modules/testing.nix
diff --git a/tests/default.nix b/tests/default.nix
index 70c6cd8..251b69e 100644
--- a/tests/default.nix
+++ b/tests/default.nix
@@ -16,13 +16,9 @@ let
     version' = replaceStrings ["."] ["_"] version;
   in nameValuePair "v${version'}" (kubenix.evalModules {
     modules = [
-      kubenix.testing
+      kubenix.modules.testing
 
       {
-        imports = [kubenix.k8s kubenix.submodules];
-
-        kubernetes.version = version;
-
         testing.throwError = throwError;
         testing.e2e = e2e;
         testing.tests = [
@@ -40,7 +36,7 @@ let
           ./module.nix
         ];
         testing.defaults = ({kubenix, ...}: {
-          imports = [kubenix.k8s];
+          imports = [kubenix.modules.k8s];
           kubernetes.version = version;
           _module.args.images = images;
         });
diff --git a/tests/helm/simple.nix b/tests/helm/simple.nix
index 139c2a7..98f05d5 100644
--- a/tests/helm/simple.nix
+++ b/tests/helm/simple.nix
@@ -1,4 +1,4 @@
-{ config, lib, test, pkgs, kubenix, helm, ... }:
+{ config, lib, pkgs, kubenix, helm, ... }:
 
 with lib;
 with kubenix.lib;
@@ -29,9 +29,7 @@ let
     finalImageTag = "latest";
   };
 in {
-  imports = [
-    kubenix.helm
-  ];
+  imports = [ kubenix.modules.test kubenix.modules.helm ];
 
   test = {
     name = "helm-simple";
diff --git a/tests/istio/bookinfo.nix b/tests/istio/bookinfo.nix
index bcb090c..269bca8 100644
--- a/tests/istio/bookinfo.nix
+++ b/tests/istio/bookinfo.nix
@@ -1,12 +1,7 @@
-{ config, test, kubenix, k8s, ... }:
-
-with k8s;
+{ config, kubenix, ... }:
 
 {
-  imports = [
-    kubenix.k8s
-    kubenix.istio
-  ];
+  imports = with kubenix.modules; [ test k8s istio ];
 
   test = {
     name = "istio-bookinfo";
diff --git a/tests/k8s/1.13/crd.nix b/tests/k8s/1.13/crd.nix
index 589b073..4b3b20d 100644
--- a/tests/k8s/1.13/crd.nix
+++ b/tests/k8s/1.13/crd.nix
@@ -5,9 +5,7 @@ with lib;
 let
   cfg = config.kubernetes.api.customresourcedefinitions.crontabs;
 in {
-  imports = [
-    kubenix.k8s
-  ];
+  imports = with kubenix.modules; [ test k8s ];
 
   test = {
     name = "k8s-1.13-crd";
diff --git a/tests/k8s/crd.nix b/tests/k8s/crd.nix
index 0c4c913..2fea676 100644
--- a/tests/k8s/crd.nix
+++ b/tests/k8s/crd.nix
@@ -5,9 +5,7 @@ with lib;
 let
   cfg = config.kubernetes.api.customresourcedefinitions.crontabs;
 in {
-  imports = [
-    kubenix.k8s
-  ];
+  imports = with kubenix.modules; [ test k8s ];
 
   test = {
     name = "k8s-crd";
diff --git a/tests/k8s/defaults.nix b/tests/k8s/defaults.nix
index 07d9508..8f4a8fe 100644
--- a/tests/k8s/defaults.nix
+++ b/tests/k8s/defaults.nix
@@ -1,15 +1,12 @@
-{ config, lib, test, kubenix, k8s, ... }:
+{ config, lib, kubenix, ... }:
 
 with lib;
-with k8s;
 
 let
   pod1 = config.kubernetes.api.pods.pod1;
   pod2 = config.kubernetes.api.pods.pod2;
 in {
-  imports = [
-    kubenix.k8s
-  ];
+  imports = with kubenix.modules; [ test k8s ];
 
   test = {
     name = "k8s-defaults";
diff --git a/tests/k8s/deployment.nix b/tests/k8s/deployment.nix
index e1b3919..d2288fd 100644
--- a/tests/k8s/deployment.nix
+++ b/tests/k8s/deployment.nix
@@ -1,4 +1,4 @@
-{ config, lib, pkgs, test, kubenix, images, ... }:
+{ config, lib, pkgs, kubenix, images, ... }:
 
 with lib;
 
@@ -6,9 +6,7 @@ let
   cfg = config.kubernetes.api.deployments.nginx;
   image = images.nginx;
 in {
-  imports = [
-    kubenix.k8s
-  ];
+  imports = [ kubenix.modules.test kubenix.modules.k8s ];
 
   test = {
     name = "k8s-deployment";
diff --git a/tests/k8s/order.nix b/tests/k8s/order.nix
index 5079a9e..314e820 100644
--- a/tests/k8s/order.nix
+++ b/tests/k8s/order.nix
@@ -5,9 +5,7 @@ with lib;
 let
   cfg = config.kubernetes.api.customresourcedefinitions.crontabs;
 in {
-  imports = [
-    kubenix.k8s
-  ];
+  imports = with kubenix.modules; [ test k8s ];
 
   test = {
     name = "k8s-order";
diff --git a/tests/k8s/simple.nix b/tests/k8s/simple.nix
index 07f447a..107b788 100644
--- a/tests/k8s/simple.nix
+++ b/tests/k8s/simple.nix
@@ -1,13 +1,9 @@
-{ config, test, kubenix, k8s, ... }:
-
-with k8s;
+{ config, kubenix, ... }:
 
 let
   cfg = config.kubernetes.api.pods.nginx;
 in {
-  imports = [
-    kubenix.k8s
-  ];
+  imports = [ kubenix.modules.test kubenix.modules.k8s ];
 
   test = {
     name = "k8s-simple";
diff --git a/tests/module.nix b/tests/module.nix
index b2a7ae7..4191489 100644
--- a/tests/module.nix
+++ b/tests/module.nix
@@ -6,9 +6,7 @@ let
   cfg = config.submodules.instances.test.config;
   deployment = cfg.kubernetes.api.deployments.nginx;
 in {
-  imports = [
-    kubenix.module
-  ];
+  imports = [ kubenix.modules.test kubenix.module ];
 
   test = {
     name = "module";
diff --git a/tests/submodules/defaults.nix b/tests/submodules/defaults.nix
index 7b662d4..32d0838 100644
--- a/tests/submodules/defaults.nix
+++ b/tests/submodules/defaults.nix
@@ -21,9 +21,7 @@ let
     };
   };
 in {
-  imports = [
-    kubenix.submodules
-  ];
+  imports = with kubenix.modules; [ test submodules ];
 
   test = {
     name = "submodules-defatuls";
diff --git a/tests/submodules/simple.nix b/tests/submodules/simple.nix
index 4d967d8..c8b3c05 100644
--- a/tests/submodules/simple.nix
+++ b/tests/submodules/simple.nix
@@ -5,9 +5,7 @@ with lib;
 let
   cfg = config.submodules.instances.instance;
 in {
-  imports = [
-    kubenix.submodules
-  ];
+  imports = with kubenix.modules; [ test submodules ];
 
   test = {
     name = "submodules-simple";
diff --git a/tests/submodules/versioning.nix b/tests/submodules/versioning.nix
index d5fde23..e316b5f 100644
--- a/tests/submodules/versioning.nix
+++ b/tests/submodules/versioning.nix
@@ -16,9 +16,7 @@ let
     };
   };
 in {
-  imports = [
-    kubenix.submodules
-  ];
+  imports = with kubenix.modules; [ test submodules ];
 
   test = {
     name = "submodules-imports";