diff --git a/src/main.rs b/src/main.rs
index 399a23f..861aa58 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,4 +1,9 @@
-#![feature(generators, generator_trait, type_alias_impl_trait)]
+#![feature(
+    generators,
+    generator_trait,
+    type_alias_impl_trait,
+    impl_trait_in_assoc_type
+)]
 
 mod core;
 mod prelude;