diff --git a/src/interfaces/ComparableItem.ts b/src/interfaces/ComparableItem.ts
new file mode 100644
index 0000000..6f2ea3f
--- /dev/null
+++ b/src/interfaces/ComparableItem.ts
@@ -0,0 +1,3 @@
+export interface ComparableItem {
+  isEqual(item: unknown): boolean;
+}
diff --git a/src/interfaces/PrimitiveOf.ts b/src/interfaces/PrimitiveOf.ts
index 95d6fad..21cf0cb 100644
--- a/src/interfaces/PrimitiveOf.ts
+++ b/src/interfaces/PrimitiveOf.ts
@@ -1,11 +1,4 @@
-import { Primitive } from '../types/Primitive';
-
-type SerializedValue =
-  | Primitive
-  | SerializedValue[]
-  | {
-      [key: string]: SerializedValue;
-    };
+import { SerializedValue } from '../types/SerializedValue';
 
 export type PrimitiveOf<T extends { toPrimitives(): SerializedValue }> =
   ReturnType<T['toPrimitives']>;
diff --git a/src/interfaces/index.ts b/src/interfaces/index.ts
index ccfd63a..3102110 100644
--- a/src/interfaces/index.ts
+++ b/src/interfaces/index.ts
@@ -1 +1,2 @@
+export * from './ComparableItem';
 export * from './PrimitiveOf';
diff --git a/src/types/SerializedValue.ts b/src/types/SerializedValue.ts
new file mode 100644
index 0000000..fa34570
--- /dev/null
+++ b/src/types/SerializedValue.ts
@@ -0,0 +1,8 @@
+import { Primitive } from './Primitive';
+
+export type SerializedValue =
+  | Primitive
+  | SerializedValue[]
+  | {
+      [key: string]: SerializedValue;
+    };
diff --git a/src/types/index.ts b/src/types/index.ts
index 8a5b7a8..19e155a 100644
--- a/src/types/index.ts
+++ b/src/types/index.ts
@@ -1,2 +1,3 @@
 export * from './Primitive';
 export * from './Nullish';
+export * from './SerializedValue';
diff --git a/src/value-objects/UniqueObjectArray.ts b/src/value-objects/UniqueObjectArray.ts
index 30e805a..5b5496b 100644
--- a/src/value-objects/UniqueObjectArray.ts
+++ b/src/value-objects/UniqueObjectArray.ts
@@ -1,6 +1,4 @@
-interface ComparableItem {
-  isEqual(item: unknown): boolean;
-}
+import { ComparableItem } from '../interfaces/ComparableItem';
 
 export class UniqueObjectArray<
   T extends ComparableItem,