diff --git a/packages/dynamite/dynamite_petstore_example/lib/petstore.openapi.dart b/packages/dynamite/dynamite_petstore_example/lib/petstore.openapi.dart
index 2ca87c30..bcd08ca5 100644
--- a/packages/dynamite/dynamite_petstore_example/lib/petstore.openapi.dart
+++ b/packages/dynamite/dynamite_petstore_example/lib/petstore.openapi.dart
@@ -327,7 +327,65 @@ abstract class NewPet implements NewPetInterface, Built<NewPet, NewPetBuilder> {
   Map<String, dynamic> toJson() => _jsonSerializers.serializeWith(serializer, this)! as Map<String, dynamic>;
   // coverage:ignore-end
 
-  static Serializer<NewPet> get serializer => _$newPetSerializer;
+  @BuiltValueSerializer(custom: true)
+  static Serializer<NewPet> get serializer => _$NewPetSerializer();
+}
+
+class _$NewPetSerializer implements StructuredSerializer<NewPet> {
+  const _$NewPetSerializer();
+
+  @override
+  Iterable<Type> get types => const [NewPet, _$NewPet];
+
+  @override
+  String get wireName => r'NewPet';
+
+  @override
+  Iterable<Object?> serialize(
+    Serializers serializers,
+    NewPet object, {
+    FullType specifiedType = FullType.unspecified,
+  }) {
+    final result = <Object?>[
+      'name',
+      serializers.serialize(object.name, specifiedType: const FullType(String)),
+    ];
+    Object? value;
+    value = object.tag;
+    if (value != null) {
+      result
+        ..add('tag')
+        ..add(
+          serializers.serialize(value, specifiedType: const FullType(String)),
+        );
+    }
+
+    return result;
+  }
+
+  @override
+  NewPet deserialize(
+    Serializers serializers,
+    Iterable<Object?> serialized, {
+    FullType specifiedType = FullType.unspecified,
+  }) {
+    final result = NewPetBuilder();
+
+    final iterator = serialized.iterator;
+    while (iterator.moveNext()) {
+      final key = iterator.current! as String;
+      iterator.moveNext();
+      final value = iterator.current;
+      switch (key) {
+        case 'name':
+          result.name = (serializers.deserialize(value, specifiedType: const FullType(String))! as String);
+        case 'tag':
+          result.tag = (serializers.deserialize(value, specifiedType: const FullType(String)) as String);
+      }
+    }
+
+    return result.build();
+  }
 }
 
 @BuiltValue(instantiable: false)
@@ -377,7 +435,57 @@ abstract class Error implements ErrorInterface, Built<Error, ErrorBuilder> {
   Map<String, dynamic> toJson() => _jsonSerializers.serializeWith(serializer, this)! as Map<String, dynamic>;
   // coverage:ignore-end
 
-  static Serializer<Error> get serializer => _$errorSerializer;
+  @BuiltValueSerializer(custom: true)
+  static Serializer<Error> get serializer => _$ErrorSerializer();
+}
+
+class _$ErrorSerializer implements StructuredSerializer<Error> {
+  const _$ErrorSerializer();
+
+  @override
+  Iterable<Type> get types => const [Error, _$Error];
+
+  @override
+  String get wireName => r'Error';
+
+  @override
+  Iterable<Object?> serialize(
+    Serializers serializers,
+    Error object, {
+    FullType specifiedType = FullType.unspecified,
+  }) {
+    final result = <Object?>[
+      'code',
+      serializers.serialize(object.code, specifiedType: const FullType(int)),
+      'message',
+      serializers.serialize(object.message, specifiedType: const FullType(String)),
+    ];
+    return result;
+  }
+
+  @override
+  Error deserialize(
+    Serializers serializers,
+    Iterable<Object?> serialized, {
+    FullType specifiedType = FullType.unspecified,
+  }) {
+    final result = ErrorBuilder();
+
+    final iterator = serialized.iterator;
+    while (iterator.moveNext()) {
+      final key = iterator.current! as String;
+      iterator.moveNext();
+      final value = iterator.current;
+      switch (key) {
+        case 'code':
+          result.code = (serializers.deserialize(value, specifiedType: const FullType(int))! as int);
+        case 'message':
+          result.message = (serializers.deserialize(value, specifiedType: const FullType(String))! as String);
+      }
+    }
+
+    return result.build();
+  }
 }
 
 // coverage:ignore-start
diff --git a/packages/dynamite/dynamite_petstore_example/lib/petstore.openapi.g.dart b/packages/dynamite/dynamite_petstore_example/lib/petstore.openapi.g.dart
index 6786ccb0..30c14c1e 100644
--- a/packages/dynamite/dynamite_petstore_example/lib/petstore.openapi.g.dart
+++ b/packages/dynamite/dynamite_petstore_example/lib/petstore.openapi.g.dart
@@ -6,55 +6,7 @@ part of 'petstore.openapi.dart';
 // BuiltValueGenerator
 // **************************************************************************
 
-Serializer<NewPet> _$newPetSerializer = _$NewPetSerializer();
 Serializer<Pet> _$petSerializer = _$PetSerializer();
-Serializer<Error> _$errorSerializer = _$ErrorSerializer();
-
-class _$NewPetSerializer implements StructuredSerializer<NewPet> {
-  @override
-  final Iterable<Type> types = const [NewPet, _$NewPet];
-  @override
-  final String wireName = 'NewPet';
-
-  @override
-  Iterable<Object?> serialize(Serializers serializers, NewPet object, {FullType specifiedType = FullType.unspecified}) {
-    final result = <Object?>[
-      'name',
-      serializers.serialize(object.name, specifiedType: const FullType(String)),
-    ];
-    Object? value;
-    value = object.tag;
-    if (value != null) {
-      result
-        ..add('tag')
-        ..add(serializers.serialize(value, specifiedType: const FullType(String)));
-    }
-    return result;
-  }
-
-  @override
-  NewPet deserialize(Serializers serializers, Iterable<Object?> serialized,
-      {FullType specifiedType = FullType.unspecified}) {
-    final result = NewPetBuilder();
-
-    final iterator = serialized.iterator;
-    while (iterator.moveNext()) {
-      final key = iterator.current! as String;
-      iterator.moveNext();
-      final Object? value = iterator.current;
-      switch (key) {
-        case 'name':
-          result.name = serializers.deserialize(value, specifiedType: const FullType(String))! as String;
-          break;
-        case 'tag':
-          result.tag = serializers.deserialize(value, specifiedType: const FullType(String)) as String?;
-          break;
-      }
-    }
-
-    return result.build();
-  }
-}
 
 class _$PetSerializer implements StructuredSerializer<Pet> {
   @override
@@ -107,48 +59,6 @@ class _$PetSerializer implements StructuredSerializer<Pet> {
   }
 }
 
-class _$ErrorSerializer implements StructuredSerializer<Error> {
-  @override
-  final Iterable<Type> types = const [Error, _$Error];
-  @override
-  final String wireName = 'Error';
-
-  @override
-  Iterable<Object?> serialize(Serializers serializers, Error object, {FullType specifiedType = FullType.unspecified}) {
-    final result = <Object?>[
-      'code',
-      serializers.serialize(object.code, specifiedType: const FullType(int)),
-      'message',
-      serializers.serialize(object.message, specifiedType: const FullType(String)),
-    ];
-
-    return result;
-  }
-
-  @override
-  Error deserialize(Serializers serializers, Iterable<Object?> serialized,
-      {FullType specifiedType = FullType.unspecified}) {
-    final result = ErrorBuilder();
-
-    final iterator = serialized.iterator;
-    while (iterator.moveNext()) {
-      final key = iterator.current! as String;
-      iterator.moveNext();
-      final Object? value = iterator.current;
-      switch (key) {
-        case 'code':
-          result.code = serializers.deserialize(value, specifiedType: const FullType(int))! as int;
-          break;
-        case 'message':
-          result.message = serializers.deserialize(value, specifiedType: const FullType(String))! as String;
-          break;
-      }
-    }
-
-    return result.build();
-  }
-}
-
 abstract mixin class NewPetInterfaceBuilder {
   void replace(NewPetInterface other);
   void update(void Function(NewPetInterfaceBuilder) updates);