diff --git a/macros/src/memoize.rs b/macros/src/memoize.rs
index d6c0b10..09afbce 100644
--- a/macros/src/memoize.rs
+++ b/macros/src/memoize.rs
@@ -130,7 +130,7 @@ fn process(function: &Function) -> Result<TokenStream> {
             #output,
         > = ::comemo::internal::Cache::new(|| {
             ::comemo::internal::register_evictor(|max_age| __CACHE.evict(max_age));
-            ::std::default::Default::default()
+            ::core::default::Default::default()
         });
 
         #(#bounds;)*
diff --git a/macros/src/track.rs b/macros/src/track.rs
index e0db944..bfc90be 100644
--- a/macros/src/track.rs
+++ b/macros/src/track.rs
@@ -213,7 +213,6 @@ fn create_variants(methods: &[Method]) -> TokenStream {
         enum __ComemoVariant {
             #(#variants,)*
         }
-
     }
 }
 
@@ -291,6 +290,7 @@ fn create(
     } else {
         quote! { MutableConstraint }
     };
+
     Ok(quote! {
         impl #impl_params ::comemo::Track for #ty #where_clause {}
 
diff --git a/src/constraint.rs b/src/constraint.rs
index bec98aa..6af0732 100644
--- a/src/constraint.rs
+++ b/src/constraint.rs
@@ -135,9 +135,9 @@ impl<T: Call> MutableConstraint<T> {
     where
         F: FnMut(&T),
     {
-        for call in &self.0.read().0 {
-            if call.call.is_mutable() {
-                f(&call.call);
+        for entry in &self.0.read().0 {
+            if entry.call.is_mutable() {
+                f(&entry.call);
             }
         }
     }
@@ -245,8 +245,8 @@ impl<T: Call> Join for ImmutableConstraint<T> {
     #[inline]
     fn join(&self, inner: &Self) {
         let mut this = self.0.write();
-        for call in inner.0.read().0.values() {
-            this.push_inner(Cow::Borrowed(call));
+        for entry in inner.0.read().0.values() {
+            this.push_inner(Cow::Borrowed(entry));
         }
     }
 
@@ -260,8 +260,8 @@ impl<T: Call> Join for MutableConstraint<T> {
     #[inline]
     fn join(&self, inner: &Self) {
         let mut this = self.0.write();
-        for call in inner.0.read().0.iter() {
-            this.push_inner(Cow::Borrowed(call));
+        for entry in inner.0.read().0.iter() {
+            this.push_inner(Cow::Borrowed(entry));
         }
     }