diff --git a/juniper/src/executor/mod.rs b/juniper/src/executor/mod.rs
index 6cf83769..2026f97b 100644
--- a/juniper/src/executor/mod.rs
+++ b/juniper/src/executor/mod.rs
@@ -4,6 +4,7 @@ use std::{
     borrow::Cow,
     cmp::Ordering,
     collections::{hash_map, HashMap},
+    convert,
     fmt::{Debug, Display},
     sync::{Arc, RwLock},
 };
@@ -1297,14 +1298,12 @@ impl<'r, S: 'r> Registry<'r, S> {
         T: resolve::TypeName<TI> + resolve::InputValueOwned<S> + resolve::ScalarToken<S>,
         TI: ?Sized,
         'ti: 'r,
-        F: FnOnce(&mut ScalarMeta<'r, S>),
+        F: FnOnce(ScalarMeta<'r, S>) -> ScalarMeta<'r, S>,
         S: Clone,
     {
         self.entry_type::<T, _>(type_info)
             .or_insert_with(move || {
-                let mut scalar = ScalarMeta::new_reworked::<T, _>(T::type_name(type_info));
-                customize(&mut scalar);
-                scalar.into_meta()
+                customize(ScalarMeta::new_reworked::<T, _>(T::type_name(type_info))).into_meta()
             })
             .clone()
     }
@@ -1326,9 +1325,7 @@ impl<'r, S: 'r> Registry<'r, S> {
         'ti: 'r,
         S: Clone,
     {
-        // TODO: Use `drop` instead of `|_| {}` once Rust's inference becomes
-        //       better for HRTB closures.
-        self.register_scalar_unsized_with::<T, TI, _>(type_info, |_| {})
+        self.register_scalar_unsized_with::<T, TI, _>(type_info, convert::identity)
     }
 
     /// Builds a [`ScalarMeta`] information for the specified non-[`Sized`]
@@ -1351,14 +1348,12 @@ impl<'r, S: 'r> Registry<'r, S> {
         T: resolve::TypeName<TI> + resolve::InputValueAsRef<S> + resolve::ScalarToken<S> + ?Sized,
         TI: ?Sized,
         'ti: 'r,
-        F: FnOnce(&mut ScalarMeta<'r, S>),
+        F: FnOnce(ScalarMeta<'r, S>) -> ScalarMeta<'r, S>,
         S: Clone,
     {
         self.entry_type::<T, _>(type_info)
             .or_insert_with(move || {
-                let mut scalar = ScalarMeta::new_unsized::<T, _>(T::type_name(type_info));
-                customize(&mut scalar);
-                scalar.into_meta()
+                customize(ScalarMeta::new_unsized::<T, _>(T::type_name(type_info))).into_meta()
             })
             .clone()
     }
diff --git a/juniper_codegen/src/graphql_scalar/mod.rs b/juniper_codegen/src/graphql_scalar/mod.rs
index 35b16865..e7a9e1a1 100644
--- a/juniper_codegen/src/graphql_scalar/mod.rs
+++ b/juniper_codegen/src/graphql_scalar/mod.rs
@@ -529,9 +529,10 @@ impl Definition {
         let predicates = &mut generics.make_where_clause().predicates;
         predicates.push(parse_quote! { #sv: Clone });
         predicates.push(parse_quote! {
-            Self: ::juniper::resolve::TypeName<#inf, #bh>
-                  + ::juniper::resolve::ScalarToken<#sv, #bh>
-                  + ::juniper::resolve::InputValueOwned<#sv, #bh>
+            ::juniper::behavior::Coerce<Self, #bh>:
+                ::juniper::resolve::TypeName<#inf, #bh>
+                + ::juniper::resolve::ScalarToken<#sv, #bh>
+                + ::juniper::resolve::InputValueOwned<#sv, #bh>
         });
         let (impl_gens, _, where_clause) = generics.split_for_impl();
 
@@ -561,7 +562,7 @@ impl Definition {
                         ::juniper::behavior::Coerce<Self, #bh>, _, _,
                     >(type_info, |meta| {
                         meta#description
-                            #specified_by_url;
+                            #specified_by_url
                     })
                 }
             }