diff --git a/src/Trait.ts b/src/Trait.ts
index 16988cd..e8f5cfd 100644
--- a/src/Trait.ts
+++ b/src/Trait.ts
@@ -1,7 +1,7 @@
 import { Fn } from "hotscript"
 import { AbstractClass, Class, Simplify } from "type-fest"
 import { TraitExpression } from "./TraitExpression"
-import { Extend, StaticMembers } from "./util"
+import { Extend, ExtendPlain, StaticMembers } from "./util"
 
 
 export class Trait<
@@ -96,16 +96,18 @@ export namespace Trait {
 }
 
 export namespace Traits {
-    export type MapImplClass<T extends readonly any[]> = {
+    export type MapImplClass<T> = {
         [K in keyof T]: Trait.OwnImplClass<T[K]>
     }
 
-    export type MapImplInstance<T extends readonly any[]> = {
+    export type MapImplInstance<T> = {
         [K in keyof T]: Trait.OwnImplInstance<T[K]>
     }
 
-    export type MapImplStaticMembers<T extends readonly any[]> = {
-        [K in keyof T]: Trait.OwnImplStaticMembers<T[K]>
+    export type MapImplStaticMembers<T> = {
+        [K in keyof T]: K extends keyof []
+            ? T[K]
+            : Trait.OwnImplStaticMembers<T[K]>
     }
 }
 
@@ -122,7 +124,7 @@ export type TraitConcreteClass<T extends Trait<any, any, any, any>> = (
 
 export type TraitInstance<T extends Trait<any, any, any, any>> = (
     Simplify<
-        Extend<[
+        ExtendPlain<[
             Trait.OwnAbstract<T>,
             Trait.OwnImplInstance<T>,
         ]>
@@ -131,7 +133,7 @@ export type TraitInstance<T extends Trait<any, any, any, any>> = (
 
 export type TraitStaticMembers<T extends Trait<any, any, any, any>> = (
     Simplify<
-        Extend<[
+        ExtendPlain<[
             Trait.OwnStaticAbstract<T>,
             StaticMembers<Trait.OwnImplClass<T>>,
         ]>