Found working approach

src/TraitBuilder.ts

@@ -68,10 +68,8 @@ type MapTraitsToOwnImplInstance<T extends readonly any[]> = {
 type MapTraitsToOwnImplStaticMembers<T extends readonly any[]> = {
     [K in keyof T]: Trait.OwnImplClass<T[K]>
 }
-type MapStaticMembers<Tuple extends readonly AbstractClass<any>[]> = {
-    [TupleK in keyof Tuple]: {
-        [ClassK in keyof Tuple[TupleK]]: Tuple[TupleK][ClassK]
-    }
+type MapStaticMembers<T extends readonly AbstractClass<any>[]> = {
+    [K in keyof T]: StaticMembers<T[K]>
 }
 
 

src/tests.ts

@@ -84,19 +84,27 @@ class User extends exp.extends implements Implements<typeof exp> {
 console.log(new User())
 
 
-type ExpectsObjectArray<T extends readonly object[]> = T
+type ExpectObjectArray<T extends readonly object[]> = T
+
+type MapOwnImplClass<T extends readonly any[]> = {
+    [K in keyof T]: Trait.OwnImplClass<T[K]>
+}
 
 type MapStaticMembers<T extends readonly any[]> = {
     [K in keyof T]: StaticMembers<T[K]>
 }
 
-type MapClasses<Classes extends AbstractClass<any>[]> = (
-    ExpectsObjectArray<
-        MapStaticMembers<
-            Classes
+
+type MapClasses<Exp> = (
+    Exp extends TraitExpression<any, infer Traits>
+        ? ExpectObjectArray<
+            MapStaticMembers<
+                MapOwnImplClass<
+                    Traits
+                >
+            >
         >
-    >
+        : never
 )
 
-
-type Output = MapClasses<[typeof User]>
+type Output = MapClasses<typeof exp>