diff --git a/src/ZodSchemaClass.ts b/src/ZodSchemaClass.ts
index d2dbf62..ff4569f 100644
--- a/src/ZodSchemaClass.ts
+++ b/src/ZodSchemaClass.ts
@@ -2,16 +2,11 @@ import { Effect, pipe } from "effect"
 import { AbstractClass, Class as ConcreteClass, Opaque } from "type-fest"
 import { z } from "zod"
 import { DefinedDefaultValuesTag, NewZodSchemaInstanceArgs, NewZodSchemaInstanceInput, TZodSchemaClass } from "."
-import { Class, GetClassType, StaticMembers, parseZodTypeEffect } from "./util"
+import { Class, GetClassType, MergeInheritanceTree, MergeInheritanceTreeWithoutOverriding, StaticMembers, parseZodTypeEffect } from "./util"
 
 
-type ExtendableClass = AbstractClass<any, []> & {
-    schema?:         never
-    defaultValues?:  never
-}
-
 export function ZodSchemaClassOf<
-    Parent            extends ExtendableClass,
+    Parent            extends AbstractClass<any, []>,
 
     SchemaT           extends z.ZodRawShape,
     SchemaUnknownKeys extends z.UnknownKeysParam,
@@ -114,14 +109,18 @@ export function ZodSchemaClassOf<
         Class<
             GetClassType<Parent>,
 
-            InstanceType<Parent> &
-            InstanceType<TZodSchemaClassImpl>,
+            MergeInheritanceTreeWithoutOverriding<[
+                InstanceType<Parent>,
+                InstanceType<TZodSchemaClassImpl>,
+            ]> &
 
             ConstructorParameters<TZodSchemaClassImpl>
         > &
 
-        StaticMembers<Parent> &
-        StaticMembers<TZodSchemaClassImpl>
+        MergeInheritanceTree<[
+            StaticMembers<Parent>,
+            StaticMembers<TZodSchemaClassImpl>,
+        ]>
     )
 }