diff --git a/lib/types/default.nix b/lib/types/default.nix
new file mode 100644
index 00000000..a5a8b178
--- /dev/null
+++ b/lib/types/default.nix
@@ -0,0 +1,30 @@
+{
+  lib,
+  dream2nix,
+  specialArgs,
+  ...
+}: let
+  t = lib.types;
+in rec {
+  derivation = t.oneOf [t.str t.path t.package];
+
+  # A stricteer submodule type that prevents derivations from being
+  # detected as modules by accident. (derivations are attrs as well as modules)
+  drvPart = let
+    type = t.submoduleWith {
+      modules = [dream2nix.modules.dream2nix.core];
+      inherit specialArgs;
+    };
+  in
+    type
+    // {
+      # Ensure that derivations are never detected as modules by accident.
+      check = val: type.check val && (val.type or null != "derivation");
+    };
+
+  # polymorphic type, that can either represent a derivation or a drv-part.
+  # The stricter`drvPart` type is needed to prevent derivations being
+  #   classified as modules by accident.
+  # This is important because derivations cannot be merged with drv-parts.
+  drvPartOrPackage = t.either derivation drvPart;
+}
diff --git a/modules/dream2nix/WIP-nodejs-builder-v3/types.nix b/modules/dream2nix/WIP-nodejs-builder-v3/types.nix
index 4ad58aeb..67187e65 100644
--- a/modules/dream2nix/WIP-nodejs-builder-v3/types.nix
+++ b/modules/dream2nix/WIP-nodejs-builder-v3/types.nix
@@ -10,23 +10,9 @@
   l = lib // builtins;
   t = l.types;
 
-  derivationType = t.oneOf [t.str t.path t.package];
-
-  # A stricter submodule type that prevents derivations from being
-  # detected as modules by accident. (derivations are attrs as well as modules)
-  drvPart = let
-    type = t.submoduleWith {
-      modules = [dream2nix.modules.dream2nix.core];
-      inherit specialArgs;
-    };
-  in
-    type
-    // {
-      # Ensure that derivations are never detected as modules by accident.
-      check = val: type.check val && (val.type or null != "derivation");
-    };
-
-  drvPartOrPackage = t.either derivationType drvPart;
+  dreamTypes = import ../../../lib/types {
+    inherit dream2nix lib specialArgs;
+  };
 
   # optPackage = l.mkOption {
   #   # type = t.raw;
@@ -35,7 +21,7 @@
   #   # default = null;
   # };
   optOptionalPackage = l.mkOption {
-    type = t.nullOr drvPartOrPackage;
+    type = t.nullOr dreamTypes.drvPartOrPackage;
     apply = drv: drv.public or drv;
     default = null;
   };
@@ -144,7 +130,7 @@ in {
   fileSystem = {
     type = t.nullOr (t.attrsOf (t.submodule {
       options.source = l.mkOption {
-        type = t.nullOr drvPartOrPackage;
+        type = t.nullOr dreamTypes.drvPartOrPackage;
       };
       options.bins = optBins;
     }));
diff --git a/modules/dream2nix/mkDerivation/interface.nix b/modules/dream2nix/mkDerivation/interface.nix
index aebab952..bae8d433 100644
--- a/modules/dream2nix/mkDerivation/interface.nix
+++ b/modules/dream2nix/mkDerivation/interface.nix
@@ -10,32 +10,14 @@
 
   common-options = import ../builtins-derivation/derivation-common/options.nix {inherit lib;};
 
-  derivationType = t.oneOf [t.str t.path t.package];
-
-  # A stricteer submodule type that prevents derivations from being
-  # detected as modules by accident. (derivations are attrs as well as modules)
-  drvPart = let
-    type = t.submoduleWith {
-      modules = [dream2nix.modules.dream2nix.core];
-      inherit specialArgs;
-    };
-  in
-    type
-    // {
-      # Ensure that derivations are never detected as modules by accident.
-      check = val: type.check val && (val.type or null != "derivation");
-    };
-
-  # polymorphic type, that can either represent a derivation or a drv-part.
-  # The stricter`drvPart` type is needed to prevent derivations being
-  #   classified as modules by accident.
-  # This is important because derivations cannot be merged with drv-parts.
-  drvPartOrPackage = t.either derivationType drvPart;
+  dreamTypes = import ../../../lib/types {
+    inherit dream2nix lib specialArgs;
+  };
 
   # Accepts either a derivation or a drv-parts submodule.
   # Uses `apply` to automatically convert drv-parts to derivations.
   optPackage = l.mkOption {
-    type = t.nullOr drvPartOrPackage;
+    type = t.nullOr dreamTypes.drvPartOrPackage;
     apply = drv: drv.public or drv;
     default = null;
   };
diff --git a/modules/dream2nix/nodejs-package-lock-v3/interface.nix b/modules/dream2nix/nodejs-package-lock-v3/interface.nix
index e045273d..5004dbfb 100644
--- a/modules/dream2nix/nodejs-package-lock-v3/interface.nix
+++ b/modules/dream2nix/nodejs-package-lock-v3/interface.nix
@@ -14,26 +14,12 @@
   t = l.types;
   cfg = config.nodejs-package-lock-v3;
 
-  derivationType = t.oneOf [t.str t.path t.package];
-
-  # A stricteer submodule type that prevents derivations from being
-  # detected as modules by accident. (derivations are attrs as well as modules)
-  drvPart = let
-    type = t.submoduleWith {
-      modules = [dream2nix.modules.dream2nix.core];
-      inherit specialArgs;
-    };
-  in
-    type
-    // {
-      # Ensure that derivations are never detected as modules by accident.
-      check = val: type.check val && (val.type or null != "derivation");
-    };
-
-  drvPartOrPackage = t.either derivationType drvPart;
+  dreamTypes = import ../../../lib/types {
+    inherit dream2nix lib specialArgs;
+  };
 
   optPackage = l.mkOption {
-    type = drvPartOrPackage;
+    type = dreamTypes.drvPartOrPackage;
     apply = drv: drv.public or drv;
     # default = null;
   };