diff --git a/src/effect.ts b/src/effect.ts
index 2602d5b..4ef1242 100644
--- a/src/effect.ts
+++ b/src/effect.ts
@@ -1,14 +1,14 @@
 import { Schema as S } from "@effect/schema"
-import { AbstractClass, Simplify } from "type-fest"
+import { Simplify } from "type-fest"
 import { Trait, TraitTuple } from "./Trait"
 import { TraitExpression } from "./TraitExpression"
-import { Extend, StaticMembers } from "./util"
+import { Extend } from "./util"
 
 
 export function extendsEffectSchemaExpression<
     Fields extends S.Struct.Fields,
     A, I, R, C,
-    Inherited,
+    Inherited extends object,
     Proto,
 
     const Traits extends readonly Trait<any, any, any, any>[],
@@ -19,20 +19,19 @@ export function extendsEffectSchemaExpression<
     >
 ) {
     return <Self>(): (
-        AbstractClass<
-            InstanceType<
-                S.Class<Self, Fields, A, I, R, C, Inherited, Proto>
-            > &
+        S.Class<
+            Self,
+            Fields,
+            A, I, R, C,
             Simplify<
-                Extend<TraitTuple.MapImplInstance<Traits>>
+                Extend<[
+                    Inherited,
+                    ...TraitTuple.MapImplInstance<Traits>
+                ]>
             >,
-
-            ConstructorParameters<S.Class<Self, Fields, A, I, R, C, Inherited, Proto>>
+            Proto
         > &
 
-        StaticMembers<
-            S.Class<Self, Fields, A, I, R, C, Inherited, Proto>
-        > &
         Simplify<
             Extend<TraitTuple.MapImplStaticMembers<Traits>>
         >