diff --git a/src/gen.rs b/src/gen.rs
index e382f64..9310074 100644
--- a/src/gen.rs
+++ b/src/gen.rs
@@ -270,7 +270,7 @@ fn gen_header(
 
         if !trait_def.supertraits.is_empty() {
             let supertraits = &trait_def.supertraits;
-            out.extend(quote! { #self_ty: #supertraits, });
+            out.extend(quote! { #proxy_ty_param: #supertraits, });
         }
         if let Some(predicates) = where_clause.map(|c| &c.predicates) {
             out.extend(predicates.into_token_stream());
diff --git a/tests/compile-fail/super_trait_not_implemented.stderr b/tests/compile-fail/super_trait_not_implemented.stderr
index 52513b6..1b65dd5 100644
--- a/tests/compile-fail/super_trait_not_implemented.stderr
+++ b/tests/compile-fail/super_trait_not_implemented.stderr
@@ -1,22 +1,27 @@
-error[E0277]: the trait bound `Box<Dog>: Supi` is not satisfied
-  --> tests/compile-fail/super_trait_not_implemented.rs:18:18
-   |
-18 |     requires_foo(Box::new(Dog)); // shouldn't, because `Box<Dog>: Supi` is not satisfied
-   |     ------------ ^^^^^^^^^^^^^ the trait `Supi` is not implemented for `Box<Dog>`
-   |     |
-   |     required by a bound introduced by this call
-   |
-   = help: the trait `Supi` is implemented for `Dog`
-note: required for `Box<Dog>` to implement `Foo`
-  --> tests/compile-fail/super_trait_not_implemented.rs:5:1
-   |
-5  | #[auto_impl(Box, &)]
-   | ^^^^^^^^^^^^^^^^^^^^
-6  | trait Foo: Supi {}
-   |       ^^^  ---- unsatisfied trait bound introduced here
-note: required by a bound in `requires_foo`
-  --> tests/compile-fail/super_trait_not_implemented.rs:14:20
-   |
-14 | fn requires_foo<T: Foo>(_: T) {}
-   |                    ^^^ required by this bound in `requires_foo`
-   = note: this error originates in the attribute macro `auto_impl` (in Nightly builds, run with -Z macro-backtrace for more info)
+error[E0277]: the trait bound `Box<T>: Supi` is not satisfied
+ --> tests/compile-fail/super_trait_not_implemented.rs:5:1
+  |
+5 | #[auto_impl(Box, &)]
+  | ^^^^^^^^^^^^^^^^^^^^ the trait `Supi` is not implemented for `Box<T>`
+  |
+  = help: the trait `Supi` is implemented for `Dog`
+note: required by a bound in `Foo`
+ --> tests/compile-fail/super_trait_not_implemented.rs:6:12
+  |
+6 | trait Foo: Supi {}
+  |            ^^^^ required by this bound in `Foo`
+  = note: this error originates in the attribute macro `auto_impl` (in Nightly builds, run with -Z macro-backtrace for more info)
+
+error[E0277]: the trait bound `&'a T: Supi` is not satisfied
+ --> tests/compile-fail/super_trait_not_implemented.rs:5:1
+  |
+5 | #[auto_impl(Box, &)]
+  | ^^^^^^^^^^^^^^^^^^^^ the trait `Supi` is not implemented for `&'a T`
+  |
+  = help: the trait `Supi` is implemented for `Dog`
+note: required by a bound in `Foo`
+ --> tests/compile-fail/super_trait_not_implemented.rs:6:12
+  |
+6 | trait Foo: Supi {}
+  |            ^^^^ required by this bound in `Foo`
+  = note: this error originates in the attribute macro `auto_impl` (in Nightly builds, run with -Z macro-backtrace for more info)
diff --git a/tests/compile-pass/super_trait_associated_type.rs b/tests/compile-pass/super_trait_associated_type.rs
new file mode 100644
index 0000000..a2f47d5
--- /dev/null
+++ b/tests/compile-pass/super_trait_associated_type.rs
@@ -0,0 +1,14 @@
+use auto_impl::auto_impl;
+
+#[auto_impl(Box, &)]
+trait Supi {
+    type Assoc;
+}
+
+#[auto_impl(Box, &)]
+trait Foo: Supi {
+    fn foo(&self, x: Self::Assoc) -> String;
+}
+
+
+fn main() {}
diff --git a/tests/compile-pass/super_trait_complex_for_refs.rs b/tests/compile-pass/super_trait_complex_for_refs.rs
index 1be1ef6..5d3def7 100644
--- a/tests/compile-pass/super_trait_complex_for_refs.rs
+++ b/tests/compile-pass/super_trait_complex_for_refs.rs
@@ -1,5 +1,6 @@
 use auto_impl::auto_impl;
 
+#[auto_impl(Box, &)]
 trait Supi<'a, T> {
     fn supi(&self);
 }
diff --git a/tests/compile-pass/super_trait_simple_for_refs.rs b/tests/compile-pass/super_trait_simple_for_refs.rs
index a1a8018..18a56f9 100644
--- a/tests/compile-pass/super_trait_simple_for_refs.rs
+++ b/tests/compile-pass/super_trait_simple_for_refs.rs
@@ -1,5 +1,6 @@
 use auto_impl::auto_impl;
 
+#[auto_impl(Box, &)]
 trait Supi {}
 
 #[auto_impl(Box, &)]