src/effect/schema/class/Mutable.ts

@@ -39,6 +39,18 @@ extends Omit<
 }
 
 
+type MutableInput<
+    Self,
+    Fields extends Schema.Struct.Fields,
+    I, R, C,
+    Inherited,
+    Proto
+> = Omit<Schema.Class<Self, Fields, I, R, C, Inherited, Proto>,
+    | "extend"
+    | "transformOrFail"
+    | "transformOrFailFrom"
+>
+
 export const Mutable = <
     Self,
     Fields extends Schema.Struct.Fields,
@@ -46,5 +58,5 @@ export const Mutable = <
     Inherited,
     Proto
 >(
-    self: Schema.Class<Self, Fields, I, R, C, Inherited, Proto>
+    self: MutableInput<Self, Fields, I, R, C, Inherited, Proto>
 ) => self as MutableClass<Self, Fields, I, R, C, Inherited, Proto>