diff --git a/compiler/can/src/annotation.rs b/compiler/can/src/annotation.rs
index f42771477b..15aae6e108 100644
--- a/compiler/can/src/annotation.rs
+++ b/compiler/can/src/annotation.rs
@@ -14,6 +14,7 @@ pub struct Annotation {
     pub introduced_variables: IntroducedVariables,
     pub references: MutSet<Symbol>,
     pub aliases: SendMap<Symbol, Alias>,
+    // pub host_exposed_aliases: SendMap<Symbol, Variable>,
     pub variably_sized_types: VariablySizedTypes,
 }
 
diff --git a/compiler/constrain/src/uniq.rs b/compiler/constrain/src/uniq.rs
index 2311ae184a..aa78ec0f12 100644
--- a/compiler/constrain/src/uniq.rs
+++ b/compiler/constrain/src/uniq.rs
@@ -2115,7 +2115,6 @@ fn annotation_to_attr_type(
         }
         HostExposedAlias {
             name: symbol,
-            def_name,
             arguments: fields,
             actual_var,
             actual,
@@ -2141,7 +2140,6 @@ fn annotation_to_attr_type(
 
                 let alias = Type::HostExposedAlias {
                     name: *symbol,
-                    def_name: *def_name,
                     arguments: new_fields,
                     actual_var: *actual_var,
                     actual: Box::new(actual_type),
diff --git a/compiler/types/src/solved_types.rs b/compiler/types/src/solved_types.rs
index c7aa099d77..5ecb986997 100644
--- a/compiler/types/src/solved_types.rs
+++ b/compiler/types/src/solved_types.rs
@@ -55,7 +55,6 @@ pub enum SolvedType {
 
     HostExposedAlias {
         name: Symbol,
-        def_name: Symbol,
         arguments: Vec<(Lowercase, SolvedType)>,
         actual_var: VarId,
         actual: Box<SolvedType>,
@@ -204,7 +203,6 @@ impl SolvedType {
             }
             HostExposedAlias {
                 name,
-                def_name,
                 arguments,
                 actual_var,
                 actual,
@@ -218,7 +216,6 @@ impl SolvedType {
 
                 SolvedType::HostExposedAlias {
                     name: *name,
-                    def_name: *def_name,
                     arguments: solved_args,
                     actual_var: VarId::from_var(*actual_var, solved_subs.inner()),
                     actual: Box::new(solved_type),
@@ -518,7 +515,6 @@ pub fn to_type(
         }
         HostExposedAlias {
             name,
-            def_name,
             arguments: solved_type_variables,
             actual_var,
             actual: solved_actual,
@@ -533,7 +529,6 @@ pub fn to_type(
 
             Type::HostExposedAlias {
                 name: *name,
-                def_name: *def_name,
                 arguments: type_variables,
                 actual_var: var_id_to_flex_var(*actual_var, free_vars, var_store),
                 actual: Box::new(actual),
diff --git a/compiler/types/src/types.rs b/compiler/types/src/types.rs
index 88d45b23c6..09cc96cea2 100644
--- a/compiler/types/src/types.rs
+++ b/compiler/types/src/types.rs
@@ -145,7 +145,6 @@ pub enum Type {
     Alias(Symbol, Vec<(Lowercase, Type)>, Box<Type>),
     HostExposedAlias {
         name: Symbol,
-        def_name: Symbol,
         arguments: Vec<(Lowercase, Type)>,
         actual_var: Variable,
         actual: Box<Type>,