diff --git a/crates/graph/src/lib.rs b/crates/graph/src/lib.rs
index 7afa962..ff7070d 100644
--- a/crates/graph/src/lib.rs
+++ b/crates/graph/src/lib.rs
@@ -36,7 +36,7 @@ pub trait Synchronicity: 'static {
     fn make_update_result<'a>() -> Self::UpdateResult<'a>;
 }
 
-pub enum Synchronous {}
+pub struct Synchronous;
 
 impl Synchronicity for Synchronous {
     type UpdateFn = Box<dyn Fn(&mut Box<dyn Any>) -> ()>;
@@ -53,7 +53,7 @@ impl Synchronicity for Synchronous {
     fn make_update_result<'a>() -> Self::UpdateResult<'a> {}
 }
 
-pub enum Asynchronous {}
+pub struct Asynchronous;
 
 impl Synchronicity for Asynchronous {
     type UpdateFn =
@@ -480,7 +480,7 @@ impl<V: Clone + 'static, S: Synchronicity> Node<V, S> for ConstNode<V, S> {
 
     fn visit_inputs(&self, _visitor: &mut dyn FnMut(NodeIndex<u32>) -> ()) {}
 
-    fn update(&mut self) -> <S as Synchronicity>::UpdateResult<'_> {
+    fn update(&mut self) -> S::UpdateResult<'_> {
         unreachable!()
     }
 
@@ -526,7 +526,7 @@ impl<R: Rule, S: Synchronicity> Node<R::Output, S> for RuleNode<R, R::Output, S>
         self.rule.visit_inputs(&mut InputIndexVisitor(visitor));
     }
 
-    fn update(&mut self) -> <S as Synchronicity>::UpdateResult<'_> {
+    fn update(&mut self) -> S::UpdateResult<'_> {
         let new_value = self.rule.evaluate();
         self.valid = true;
         *self.value.borrow_mut() = Some(new_value);