diff --git a/pkg/dart2wasm/lib/class_info.dart b/pkg/dart2wasm/lib/class_info.dart
index 205857534d5..793ebeacd1c 100644
--- a/pkg/dart2wasm/lib/class_info.dart
+++ b/pkg/dart2wasm/lib/class_info.dart
@@ -373,6 +373,14 @@ class ClassInfoCollector {
         // conservative and mark it as not being final.
         struct.hasAnySubtypes = true;
       }
+
+      if (translator.isDynamicModule) {
+        final brandIndex =
+            translator.dynamicModuleInfo!.classMetadata[cls]?.brandIndex;
+        if (brandIndex != null) {
+          translator.typesBuilder.addBrandTypeAssignment(struct, brandIndex);
+        }
+      }
     }
     translator.classesSupersFirst.add(info);
     translator.classInfo[cls] = info;
@@ -700,9 +708,10 @@ class ClassIdNumbering {
     final implementors = <Class, List<Class>>{};
     final classIds = <Class, ClassId>{};
 
-    final savedMapping = translator.dynamicModuleInfo?.classIdMapping;
-    if (savedMapping != null) {
-      savedMapping.forEach((cls, classId) {
+    if (translator.isDynamicModule) {
+      final savedMapping = translator.dynamicModuleInfo!.classMetadata;
+      savedMapping.forEach((cls, info) {
+        final classId = info.classId;
         classIds[cls] = AbsoluteClassId(classId);
         savedMaxClassId = max(savedMaxClassId ?? -2, classId);
         if (!cls.isAbstract && !cls.isAnonymousMixin) {
@@ -796,8 +805,7 @@ class ClassIdNumbering {
     }
 
     // Make a list of the depth-first pre-order traversal.
-    final dfsOrder =
-        translator.dynamicModuleInfo?.dfsOrderClassIds ?? <Class>[];
+    final dfsOrder = [...?translator.dynamicModuleInfo?.dfsOrderClassIds];
     final inDfsOrder = {...dfsOrder};
 
     // Maps any class to a dense range of concrete class ids that are subclasses
@@ -907,6 +915,9 @@ final class AbsoluteClassId extends ClassId {
   int get _localValue => value;
 
   AbsoluteClassId(this.value);
+
+  @override
+  String toString() => 'Absolute($value)';
 }
 
 final class RelativeClassId extends ClassId {
@@ -915,6 +926,9 @@ final class RelativeClassId extends ClassId {
   int get _localValue => relativeValue;
 
   RelativeClassId(this.relativeValue);
+
+  @override
+  String toString() => 'Relative($relativeValue)';
 }
 
 // A range of class ids, both ends inclusive.
diff --git a/pkg/dart2wasm/lib/compile.dart b/pkg/dart2wasm/lib/compile.dart
index 0db0f782576..caf300dc752 100644
--- a/pkg/dart2wasm/lib/compile.dart
+++ b/pkg/dart2wasm/lib/compile.dart
@@ -158,17 +158,7 @@ Future<CompilationResult> compileToModule(
     compilerOptions.compileSdk = true;
   }
 
-  DynamicModuleMetadata? dynamicModuleMetadata;
   final dynamicMainModuleUri = options.dynamicModuleMainUri;
-  if (dynamicMainModuleUri != null && options.dynamicInterfaceUri == null) {
-    final filename = options.dynamicModuleMetadataFile ??
-        Uri.parse(
-            path.setExtension(dynamicMainModuleUri.toFilePath(), '.dyndata'));
-    final dynamicModuleMetadataBytes =
-        await File.fromUri(filename).readAsBytes();
-    final source = BinaryDataSource(dynamicModuleMetadataBytes);
-    dynamicModuleMetadata = DynamicModuleMetadata.deserialize(source);
-  }
 
   final dynamicModuleMainUri = await resolveUri(options.dynamicModuleMainUri);
   final dynamicInterfaceUri = await resolveUri(options.dynamicInterfaceUri);
@@ -177,10 +167,7 @@ Future<CompilationResult> compileToModule(
   final isDynamicModule =
       dynamicModuleMainUri != null && dynamicInterfaceUri == null;
   if (isDynamicModule) {
-    dynamicModuleMetadata!.verifyDynamicModuleOptions(options);
     compilerOptions.additionalDills.add(dynamicModuleMainUri);
-  } else if (isDynamicMainModule) {
-    DynamicModuleMetadata.verifyMainModuleOptions(options);
   }
 
   CompilerResult? compilerResult;
@@ -268,7 +255,20 @@ Future<CompilationResult> compileToModule(
 
   moduleStrategy.prepareComponent();
 
-  if (isDynamicMainModule) {
+  MainModuleMetadata mainModuleMetadata =
+      MainModuleMetadata.empty(options.translatorOptions, options.environment);
+
+  if (isDynamicModule) {
+    final filename = options.dynamicModuleMetadataFile ??
+        Uri.parse(
+            path.setExtension(dynamicMainModuleUri!.toFilePath(), '.dyndata'));
+    final dynamicModuleMetadataBytes =
+        await File.fromUri(filename).readAsBytes();
+    final source = DataDeserializer(dynamicModuleMetadataBytes, component);
+    mainModuleMetadata = MainModuleMetadata.deserialize(source);
+    mainModuleMetadata.verifyDynamicModuleOptions(options);
+  } else if (isDynamicMainModule) {
+    MainModuleMetadata.verifyMainModuleOptions(options);
     writeComponentToBinary(component, dynamicModuleMainUri.path,
         includeSource: false);
   }
@@ -301,9 +301,13 @@ Future<CompilationResult> compileToModule(
 
   final moduleOutputData = moduleStrategy.buildModuleOutputData();
 
+  if (isDynamicMainModule) {
+    mainModuleMetadata.initialize(component, coreTypes);
+  }
+
   var translator = Translator(component, coreTypes, libraryIndex, recordClasses,
       moduleOutputData, options.translatorOptions,
-      dynamicModuleMetadata: dynamicModuleMetadata,
+      mainModuleMetadata: mainModuleMetadata,
       enableDynamicModules: dynamicModuleMainUri != null);
 
   String? depFile = options.depFile;
@@ -341,9 +345,9 @@ Future<CompilationResult> compileToModule(
     final filename = options.dynamicModuleMetadataFile ??
         Uri.parse(
             path.setExtension(dynamicMainModuleUri!.toFilePath(), '.dyndata'));
-    final sink = BinaryDataSink();
-    translator.dynamicModuleInfo!.toMetadata(options).serialize(sink);
-    await File.fromUri(filename).writeAsBytes(sink.takeBytes());
+    final serializer = DataSerializer(translator.component);
+    translator.dynamicModuleInfo!.metadata.serialize(translator, serializer);
+    await File.fromUri(filename).writeAsBytes(serializer.takeBytes());
   }
 
   return CompilationSuccess(wasmModules, jsRuntime, supportJs);
diff --git a/pkg/dart2wasm/lib/dispatch_table.dart b/pkg/dart2wasm/lib/dispatch_table.dart
index fb8cc2e50fb..5ab4a460432 100644
--- a/pkg/dart2wasm/lib/dispatch_table.dart
+++ b/pkg/dart2wasm/lib/dispatch_table.dart
@@ -397,7 +397,8 @@ class DispatchTable {
         (_dynamicMethods[member.name.text] ??= {}).add(selector);
       }
     }
-    final mainModuleIds = translator.dynamicModuleInfo?.selectorIds?[member];
+
+    final mainModuleIds = translator.dynamicModuleInfo?.selectorIds[member];
     if (mainModuleIds != null) {
       selector._mainModuleIds[member] =
           isGetter ? mainModuleIds.$1 : mainModuleIds.$2;
diff --git a/pkg/dart2wasm/lib/dynamic_module_kernel_metadata.dart b/pkg/dart2wasm/lib/dynamic_module_kernel_metadata.dart
index d7afdb63ed8..52c8cb360c6 100644
--- a/pkg/dart2wasm/lib/dynamic_module_kernel_metadata.dart
+++ b/pkg/dart2wasm/lib/dynamic_module_kernel_metadata.dart
@@ -3,8 +3,15 @@
 // BSD-style license that can be found in the LICENSE file.
 
 import 'package:kernel/ast.dart';
+import 'package:kernel/core_types.dart';
+import 'package:vm/metadata/procedure_attributes.dart'
+    show ProcedureAttributesMetadataRepository;
 
+import 'class_info.dart';
 import 'compiler_options.dart';
+import 'dynamic_modules.dart';
+import 'intrinsics.dart' show MemberIntrinsic;
+import 'reference_extensions.dart';
 import 'serialization.dart';
 import 'translator.dart';
 
@@ -30,24 +37,41 @@ class DynamicModuleGlobalIdRepository extends MetadataRepository<int> {
   void writeToBinary(int globalId, Node node, BinarySink sink) {}
 }
 
+class ClassMetadata {
+  final int classId;
+  final int? brandIndex;
+
+  ClassMetadata(this.classId, this.brandIndex);
+
+  factory ClassMetadata.deserialize(DataDeserializer source) {
+    final classId = source.readInt() - 1;
+    final brandIndex = source.readInt();
+    return ClassMetadata(classId, brandIndex == 0 ? null : brandIndex - 1);
+  }
+
+  void serialize(DataSerializer sink) {
+    sink.writeInt(classId + 1);
+    sink.writeInt(brandIndex == null ? 0 : brandIndex! + 1);
+  }
+}
+
 /// Metadata produced by the main module.
 ///
 /// This data will get serialized as part of the main module compilation process
 /// and will be provided as an input to be deserialized by subsequent dynamic
 /// module compilations.
-class DynamicModuleMetadata {
-  /// Global kernel class ID to dart2wasm class hierarchy class ID.
-  final Map<int, int> classIds;
+class MainModuleMetadata {
+  /// Class to metadata about the class
+  final Map<Class, ClassMetadata> classMetadata;
 
-  /// Global kernel member ID to getter and setter/method selector ID.
-  final Map<int, (int, int)> selectorIds;
+  /// Member to getter and setter/method selector ID.
+  final Map<Member, (int, int)> selectorIds;
 
   /// Global kernel class IDs in class hierarchy dfs order.
-  final List<int> dfsOrderClassIds;
+  final List<Class> dfsOrderClassIds;
 
-  /// References for all targets callable from the main module represented as
-  /// member global ID and reference type.
-  final List<(int, int)> callableReferences;
+  /// References for all targets callable from the main module.
+  final Set<Reference> callableReferences;
 
   /// Key names of updateable functions defined in the main module.
   final Map<String, int> updateableFunctionsInMain;
@@ -57,8 +81,8 @@ class DynamicModuleMetadata {
   final TranslatorOptions mainModuleTranslatorOptions;
   final Map<String, String> mainModuleEnvironment;
 
-  DynamicModuleMetadata(
-      this.classIds,
+  MainModuleMetadata._(
+      this.classMetadata,
       this.selectorIds,
       this.dfsOrderClassIds,
       this.callableReferences,
@@ -66,26 +90,78 @@ class DynamicModuleMetadata {
       this.mainModuleTranslatorOptions,
       this.mainModuleEnvironment);
 
-  void serialize(BinaryDataSink sink) {
-    sink.writeInt(classIds.length);
-    classIds.forEach((globalClassId, classId) {
-      sink.writeInt(globalClassId);
-      sink.writeClassId(classId);
+  MainModuleMetadata.empty(
+      this.mainModuleTranslatorOptions, this.mainModuleEnvironment)
+      : classMetadata = {},
+        selectorIds = {},
+        dfsOrderClassIds = [],
+        callableReferences = {},
+        updateableFunctionsInMain = {};
+
+  void initialize(Component component, CoreTypes coreTypes) {
+    _initializeCallableReferences(component, coreTypes);
+  }
+
+  void finalize(Translator translator) {
+    translator.classInfo.forEach((cls, info) {
+      final id =
+          cls.isAnonymousMixin ? -1 : (info.classId as AbsoluteClassId).value;
+      final structType = info.struct;
+      final brandIndex =
+          translator.typesBuilder.brandTypeAssignments[structType];
+      classMetadata[cls] = ClassMetadata(id, brandIndex);
+    });
+
+    final procedureMetadata =
+        (translator.component.metadata["vm.procedure-attributes.metadata"]
+                as ProcedureAttributesMetadataRepository)
+            .mapping;
+    for (final library in translator.libraries) {
+      for (final cls in library.classes) {
+        for (final member in cls.procedures) {
+          if (!member.isInstanceMember) continue;
+          selectorIds[member] = (
+            procedureMetadata[member]!.getterSelectorId,
+            procedureMetadata[member]!.methodOrSetterSelectorId
+          );
+        }
+        for (final member in cls.fields) {
+          if (!member.isInstanceMember) continue;
+          selectorIds[member] = (
+            procedureMetadata[member]!.getterSelectorId,
+            procedureMetadata[member]!.methodOrSetterSelectorId
+          );
+        }
+      }
+    }
+
+    for (final cls in translator.classIdNumbering.dfsOrder) {
+      dfsOrderClassIds.add(cls);
+    }
+  }
+
+  void serialize(Translator translator, DataSerializer sink) {
+    finalize(translator);
+
+    sink.writeInt(classMetadata.length);
+    classMetadata.forEach((cls, metadata) {
+      sink.writeClass(cls);
+      metadata.serialize(sink);
     });
     sink.writeInt(selectorIds.length);
-    selectorIds.forEach((globalMemberId, selectorIds) {
-      sink.writeInt(globalMemberId);
+    selectorIds.forEach((member, selectorIds) {
+      final wroteMember = sink.writeMember(member);
+      if (!wroteMember) return;
       sink.writeInt(selectorIds.$1);
       sink.writeInt(selectorIds.$2);
     });
     sink.writeInt(dfsOrderClassIds.length);
-    for (final classId in dfsOrderClassIds) {
-      sink.writeClassId(classId);
+    for (final cls in dfsOrderClassIds) {
+      sink.writeClass(cls);
     }
     sink.writeInt(callableReferences.length);
-    for (final callableMemberId in callableReferences) {
-      sink.writeInt(callableMemberId.$1);
-      sink.writeInt(callableMemberId.$2);
+    for (final reference in callableReferences) {
+      sink.writeReference(reference);
     }
     sink.writeInt(updateableFunctionsInMain.length);
     updateableFunctionsInMain.forEach((stringKey, key) {
@@ -101,33 +177,33 @@ class DynamicModuleMetadata {
     });
   }
 
-  static DynamicModuleMetadata deserialize(BinaryDataSource source) {
-    final classIdMappingLength = source.readInt();
-    final classIds = <int, int>{};
-    for (int i = 0; i < classIdMappingLength; i++) {
-      final globalClassId = source.readInt();
-      final classId = source.readClassId();
-      classIds[globalClassId] = classId;
+  static MainModuleMetadata deserialize(DataDeserializer source) {
+    final classMetadataLength = source.readInt();
+    final classMetadata = <Class, ClassMetadata>{};
+    for (int i = 0; i < classMetadataLength; i++) {
+      final cls = source.readClass();
+      final metadata = ClassMetadata.deserialize(source);
+      classMetadata[cls] = metadata;
     }
 
     final selectorIdMappingLength = source.readInt();
-    final selectorIds = <int, (int, int)>{};
+    final selectorIds = <Member, (int, int)>{};
     for (int i = 0; i < selectorIdMappingLength; i++) {
-      final globalMemberId = source.readInt();
+      final member = source.readMember();
       final getterSelectorId = source.readInt();
       final setterOrMethodSelectorId = source.readInt();
-      selectorIds[globalMemberId] =
-          (getterSelectorId, setterOrMethodSelectorId);
+      selectorIds[member] = (getterSelectorId, setterOrMethodSelectorId);
     }
-    final dfsOrderClassIdsLength = source.readInt();
-    final dfsOrderClassIds = <int>[];
-    for (int i = 0; i < dfsOrderClassIdsLength; i++) {
-      dfsOrderClassIds.add(source.readClassId());
+    final dfsOrderClassesLength = source.readInt();
+    final dfsOrderClasses = <Class>[];
+    for (int i = 0; i < dfsOrderClassesLength; i++) {
+      dfsOrderClasses.add(source.readClass());
     }
-    final callableMemberIdsLength = source.readInt();
-    final callableMemberIds = <(int, int)>[];
-    for (int i = 0; i < callableMemberIdsLength; i++) {
-      callableMemberIds.add((source.readInt(), source.readInt()));
+    final callableMembersLength = source.readInt();
+    final callableMembers = <Reference>{};
+    for (int i = 0; i < callableMembersLength; i++) {
+      final reference = source.readReference();
+      callableMembers.add(reference);
     }
     final updateableFunctionsInMainLength = source.readInt();
     final updateableFunctionsInMain = <String, int>{};
@@ -145,11 +221,11 @@ class DynamicModuleMetadata {
       mainModuleEnvironment[key] = value;
     }
 
-    return DynamicModuleMetadata(
-        classIds,
+    return MainModuleMetadata._(
+        classMetadata,
         selectorIds,
-        dfsOrderClassIds,
-        callableMemberIds,
+        dfsOrderClasses,
+        callableMembers,
         updateableFunctionsInMain,
         mainModuleTranslatorOptions,
         mainModuleEnvironment);
@@ -253,4 +329,63 @@ class DynamicModuleMetadata {
       fail('environment mismatch');
     }
   }
+
+  void _initializeCallableReferences(Component component, CoreTypes coreTypes) {
+    void collectCallableReference(Reference reference) {
+      final member = reference.asMember;
+
+      if (member.isExternal) {
+        final isGeneratedIntrinsic = member is Procedure &&
+            MemberIntrinsic.fromProcedure(coreTypes, member) != null;
+        if (!isGeneratedIntrinsic) return;
+      }
+      callableReferences.add(reference);
+    }
+
+    final procedureAttributeMetadata =
+        (component.metadata["vm.procedure-attributes.metadata"]
+                as ProcedureAttributesMetadataRepository)
+            .mapping;
+    void collectCallableReferences(Member member) {
+      if (member is Procedure) {
+        collectCallableReference(member.reference);
+        if (member.isInstanceMember &&
+            member.kind == ProcedureKind.Method &&
+            procedureAttributeMetadata[member]!.hasTearOffUses) {
+          collectCallableReference(member.tearOffReference);
+        }
+      } else if (member is Field) {
+        collectCallableReference(member.getterReference);
+        if (member.hasSetter) {
+          collectCallableReference(member.setterReference!);
+        }
+      } else if (member is Constructor) {
+        if (member.enclosingClass == coreTypes.numClass ||
+            member.enclosingClass == coreTypes.boolClass ||
+            member.enclosingClass ==
+                coreTypes.index.getClass('dart:_boxed_int', 'BoxedInt') ||
+            member.enclosingClass ==
+                coreTypes.index.getClass('dart:_boxed_double', 'BoxedDouble')) {
+          return;
+        }
+        collectCallableReference(member.reference);
+        collectCallableReference(member.initializerReference);
+        collectCallableReference(member.constructorBodyReference);
+      }
+    }
+
+    for (final lib in component.libraries) {
+      for (final member in lib.members) {
+        if (!member.isDynamicModuleCallable(coreTypes)) continue;
+        collectCallableReferences(member);
+      }
+
+      for (final cls in lib.classes) {
+        for (final member in cls.members) {
+          if (!member.isDynamicModuleCallable(coreTypes)) continue;
+          collectCallableReferences(member);
+        }
+      }
+    }
+  }
 }
diff --git a/pkg/dart2wasm/lib/dynamic_modules.dart b/pkg/dart2wasm/lib/dynamic_modules.dart
index 367a8c17213..3758d9dea4e 100644
--- a/pkg/dart2wasm/lib/dynamic_modules.dart
+++ b/pkg/dart2wasm/lib/dynamic_modules.dart
@@ -6,8 +6,6 @@ import 'package:kernel/ast.dart';
 import 'package:kernel/class_hierarchy.dart';
 import 'package:kernel/core_types.dart';
 import 'package:kernel/library_index.dart';
-import 'package:vm/metadata/procedure_attributes.dart'
-    show ProcedureAttributesMetadataRepository;
 import 'package:vm/transformations/dynamic_interface_annotator.dart'
     as dynamic_interface_annotator;
 import 'package:vm/transformations/pragma.dart';
@@ -21,7 +19,6 @@ import 'dispatch_table.dart';
 import 'dynamic_module_kernel_metadata.dart';
 import 'kernel_nodes.dart';
 import 'modules.dart';
-import 'reference_extensions.dart';
 import 'target.dart';
 import 'translator.dart';
 import 'types.dart' show InstanceConstantInterfaceType;
@@ -317,22 +314,18 @@ class DynamicModuleInfo {
       translator.component.dynamicModuleEntryPoint;
   bool get isDynamicModule => dynamicEntryPoint != null;
   late final w.FunctionBuilder initFunction;
+  late final MainModuleMetadata metadata;
 
-  Map<Class, int>? _classIdMapping;
-  Map<Class, int>? get classIdMapping => _classIdMapping;
+  Map<Class, ClassMetadata> get classMetadata => metadata.classMetadata;
 
-  Map<Member, (int, int)>? _selectorIds;
-  Map<Member, (int, int)>? get selectorIds => _selectorIds;
+  Map<Member, (int, int)> get selectorIds => metadata.selectorIds;
 
-  List<Reference>? _callableReferences;
-  List<Reference>? get callableReferences => _callableReferences;
-
-  List<Class>? _dfsOrderClassIds;
-  List<Class>? get dfsOrderClassIds => _dfsOrderClassIds;
+  List<Class> get dfsOrderClassIds => metadata.dfsOrderClassIds;
 
   late final w.Global moduleIdGlobal;
 
-  final Map<String, int> _updateableDispatchKeys;
+  Map<String, int> get _updateableDispatchKeys =>
+      metadata.updateableFunctionsInMain;
   // null is used to indicate that skipDynamic was passed for this key.
   final Map<int, w.BaseFunction?> _updateableFunctions = {};
 
@@ -346,43 +339,7 @@ class DynamicModuleInfo {
   late final w.ModuleBuilder dynamicModule =
       translator.modules.firstWhere((m) => m != translator.mainModule);
 
-  DynamicModuleInfo(this.translator, DynamicModuleMetadata? serializedMetadata)
-      : _updateableDispatchKeys =
-            serializedMetadata?.updateableFunctionsInMain ?? {} {
-    if (serializedMetadata != null) {
-      assert(isDynamicModule);
-      final globalIdRepository = translator
-              .component.metadata[DynamicModuleGlobalIdRepository.repositoryTag]
-          as DynamicModuleGlobalIdRepository;
-      final Map<int, TreeNode> globalIdToNode = {};
-      globalIdRepository.mapping.forEach((node, globalId) {
-        globalIdToNode[globalId] = node;
-      });
-
-      final assignedClassIds = <Class, int>{};
-      serializedMetadata.classIds.forEach((globalId, classId) {
-        assignedClassIds[globalIdToNode[globalId] as Class] = classId;
-      });
-      _classIdMapping = assignedClassIds;
-
-      final assignedSelectorIds = <Member, (int, int)>{};
-      serializedMetadata.selectorIds.forEach((globalId, selectorIds) {
-        assignedSelectorIds[globalIdToNode[globalId] as Member] = selectorIds;
-      });
-      _selectorIds = assignedSelectorIds;
-
-      _dfsOrderClassIds = [
-        for (final globalId in serializedMetadata.dfsOrderClassIds)
-          globalIdToNode[globalId] as Class
-      ];
-
-      _callableReferences = [
-        for (final reference in serializedMetadata.callableReferences)
-          _referenceForFlag(
-              globalIdToNode[reference.$1] as Member, reference.$2)
-      ];
-    }
-  }
+  DynamicModuleInfo(this.translator, this.metadata);
 
   void initDynamicModule() {
     dynamicModule.functions.start = initFunction = dynamicModule.functions
@@ -392,6 +349,8 @@ class DynamicModuleInfo {
     // Make sure the exception tag is exported from the main module.
     translator.getExceptionTag(dynamicModule);
 
+    _generateDynamicModuleCallableReferences();
+
     if (isDynamicModule) {
       _initDynamicModuleId();
       _initModuleRtt();
@@ -426,6 +385,37 @@ class DynamicModuleInfo {
     b.global_set(moduleIdGlobal);
   }
 
+  void _generateDynamicModuleCallableReferences() {
+    final references =
+        translator.dynamicModuleInfo!.metadata.callableReferences;
+
+    for (final reference in references) {
+      final member = reference.asMember;
+
+      if (member.isInstanceMember) {
+        final selector = translator.dispatchTable.selectorForTarget(reference);
+        final targetRanges = selector
+            .targets(unchecked: false, dynamicModule: false)
+            .targetRanges
+            .followedBy(selector
+                .targets(unchecked: true, dynamicModule: false)
+                .targetRanges);
+        // Instance members are only callable if their enclosing class is
+        // allocated.
+        for (final (:range, :target) in targetRanges) {
+          if (target != reference) continue;
+          for (int classId = range.start; classId <= range.end; ++classId) {
+            translator.functions.recordClassTargetUse(classId, target);
+          }
+        }
+      } else {
+        // Generate static members immediately since they are unconditionally
+        // callable.
+        translator.functions.getFunction(reference);
+      }
+    }
+  }
+
   void finishDynamicModule() {
     _registerModuleRefs(
         isDynamicModule ? initFunction.body : translator.initFunction.body);
@@ -611,99 +601,6 @@ class DynamicModuleInfo {
     translator.convertType(
         b, updatedSignature.outputs.single, signature.outputs.single);
   }
-
-  DynamicModuleMetadata toMetadata(WasmCompilerOptions options) {
-    assert(!isDynamicModule);
-    final globalIdRepository = translator
-            .component.metadata[DynamicModuleGlobalIdRepository.repositoryTag]
-        as DynamicModuleGlobalIdRepository;
-
-    final classIdMapping = <int, int>{};
-    translator.classIdNumbering.classIds.forEach((cls, id) {
-      classIdMapping[globalIdRepository.mapping[cls]!] =
-          (id as AbsoluteClassId).value;
-    });
-
-    final selectorIdMapping = <int, (int, int)>{};
-    final procedureMetadata =
-        (translator.component.metadata["vm.procedure-attributes.metadata"]
-                as ProcedureAttributesMetadataRepository)
-            .mapping;
-    for (final library in translator.libraries) {
-      for (final cls in library.classes) {
-        for (final member in cls.procedures) {
-          if (!member.isInstanceMember) continue;
-          final globalId = globalIdRepository.mapping[member];
-          // TFA might add placeholders for removed members. We can ignore
-          // these.
-          if (globalId == null) continue;
-          selectorIdMapping[globalId] = (
-            procedureMetadata[member]!.getterSelectorId,
-            procedureMetadata[member]!.methodOrSetterSelectorId
-          );
-        }
-        for (final member in cls.fields) {
-          if (!member.isInstanceMember) continue;
-          final globalId = globalIdRepository.mapping[member];
-          // TFA might add placeholders for removed members. We can ignore
-          // these.
-          if (globalId == null) continue;
-          selectorIdMapping[globalId] = (
-            procedureMetadata[member]!.getterSelectorId,
-            procedureMetadata[member]!.methodOrSetterSelectorId
-          );
-        }
-      }
-    }
-
-    final dfsOrderClassIds = <int>[];
-    for (final cls in translator.classIdNumbering.dfsOrder) {
-      dfsOrderClassIds.add(globalIdRepository.mapping[cls]!);
-    }
-
-    final callableMemberIds = <(int, int)>[];
-    for (final export in translator.functions.dynamicModuleCallable) {
-      final exportMember = export.asMember;
-      final flag = _flagForReference(export);
-      callableMemberIds.add((globalIdRepository.mapping[exportMember]!, flag));
-    }
-    return DynamicModuleMetadata(
-        classIdMapping,
-        selectorIdMapping,
-        dfsOrderClassIds,
-        callableMemberIds,
-        _updateableDispatchKeys,
-        options.translatorOptions,
-        options.environment);
-  }
-
-  static int _flagForReference(Reference reference) {
-    if (reference.isImplicitGetter) return 0;
-    if (reference.isImplicitSetter) return 1;
-    if (reference.isTearOffReference) return 2;
-    if (reference.isConstructorBodyReference) return 3;
-    if (reference.isInitializerReference) return 4;
-    if (reference.isTypeCheckerReference) return 5;
-    if (reference.isCheckedEntryReference) return 6;
-    if (reference.isUncheckedEntryReference) return 7;
-    if (reference.isBodyReference) return 8;
-    assert(reference == reference.asMember.reference);
-    return 9;
-  }
-
-  static Reference _referenceForFlag(Member member, int flag) {
-    if (flag == 0) return (member as Field).getterReference;
-    if (flag == 1) return (member as Field).setterReference!;
-    if (flag == 2) return (member as Procedure).tearOffReference;
-    if (flag == 3) return (member as Constructor).constructorBodyReference;
-    if (flag == 4) return (member as Constructor).initializerReference;
-    if (flag == 5) return member.typeCheckerReference;
-    if (flag == 6) return member.checkedEntryReference;
-    if (flag == 7) return member.uncheckedEntryReference;
-    if (flag == 8) return member.bodyReference;
-    assert(flag == 9);
-    return member.reference;
-  }
 }
 
 /// Emits code to canonicalize the provided constant value at runtime.
diff --git a/pkg/dart2wasm/lib/functions.dart b/pkg/dart2wasm/lib/functions.dart
index 192ccef6188..bb643fc5991 100644
--- a/pkg/dart2wasm/lib/functions.dart
+++ b/pkg/dart2wasm/lib/functions.dart
@@ -3,8 +3,6 @@
 // BSD-style license that can be found in the LICENSE file.
 
 import 'package:kernel/ast.dart';
-import 'package:vm/metadata/procedure_attributes.dart'
-    show ProcedureAttributesMetadataRepository;
 import 'package:wasm_builder/wasm_builder.dart' as w;
 
 import 'class_info.dart';
@@ -12,7 +10,6 @@ import 'closures.dart';
 import 'code_generator.dart';
 import 'dispatch_table.dart';
 import 'dynamic_modules.dart';
-import 'intrinsics.dart';
 import 'reference_extensions.dart';
 import 'translator.dart';
 
@@ -37,9 +34,6 @@ class FunctionCollector {
   // if an allocation of that class is encountered
   final Map<int, List<Reference>> _pendingAllocation = {};
 
-  /// Collection of references marked as callable from dynamic modules.
-  Set<Reference> dynamicModuleCallable = {};
-
   late final WasmFunctionImporter _importedDynamicModuleFunctions =
       WasmFunctionImporter(translator, '#dmf');
 
@@ -141,10 +135,6 @@ class FunctionCollector {
       }
     }
 
-    if (translator.dynamicModuleSupportEnabled) {
-      _generateDynamicModuleCallableReferences();
-    }
-
     // Value classes are always implicitly allocated.
     recordClassAllocation(
         translator.classInfo[translator.boxedBoolClass]!.classId);
@@ -154,98 +144,6 @@ class FunctionCollector {
         translator.classInfo[translator.boxedDoubleClass]!.classId);
   }
 
-  void _generateDynamicModuleCallableReferences() {
-    final references = dynamicModuleCallable = translator.isDynamicModule
-        ? translator.dynamicModuleInfo!.callableReferences!.toSet()
-        : _generateCallableReferences();
-
-    for (final reference in references) {
-      final member = reference.asMember;
-
-      if (member.isInstanceMember) {
-        final selector = translator.dispatchTable.selectorForTarget(reference);
-        final targetRanges = selector
-            .targets(unchecked: false, dynamicModule: false)
-            .targetRanges
-            .followedBy(selector
-                .targets(unchecked: true, dynamicModule: false)
-                .targetRanges);
-        // Instance members are only callable if their enclosing class is
-        // allocated.
-        for (final (:range, :target) in targetRanges) {
-          if (target != reference) continue;
-          for (int classId = range.start; classId <= range.end; ++classId) {
-            _recordClassTargetUse(classId, target);
-          }
-        }
-      } else {
-        // Generate static members immediately since they are unconditionally
-        // callable.
-        getFunction(reference);
-      }
-    }
-  }
-
-  Set<Reference> _generateCallableReferences() {
-    assert(
-        translator.dynamicModuleSupportEnabled && !translator.isDynamicModule);
-
-    final exports = <Reference>{};
-    void collectCallableReference(Reference reference) {
-      final member = reference.asMember;
-
-      if (member.isExternal) {
-        final isGeneratedIntrinsic = member is Procedure &&
-            MemberIntrinsic.fromProcedure(translator.coreTypes, member) != null;
-        if (!isGeneratedIntrinsic) return;
-      }
-      exports.add(reference);
-    }
-
-    final procedureAttributeMetadata =
-        (translator.component.metadata["vm.procedure-attributes.metadata"]
-                as ProcedureAttributesMetadataRepository)
-            .mapping;
-    void collectCallableReferences(Member member) {
-      if (member is Procedure) {
-        collectCallableReference(member.reference);
-        if (member.isInstanceMember &&
-            member.kind == ProcedureKind.Method &&
-            procedureAttributeMetadata[member]!.hasTearOffUses) {
-          collectCallableReference(member.tearOffReference);
-        }
-      } else if (member is Field) {
-        collectCallableReference(member.getterReference);
-        if (member.hasSetter) {
-          collectCallableReference(member.setterReference!);
-        }
-      } else if (member is Constructor) {
-        if (translator.classInfo[member.enclosingClass]!.struct
-            .isSubtypeOf(translator.objectInfo.struct)) {
-          collectCallableReference(member.reference);
-          collectCallableReference(member.initializerReference);
-          collectCallableReference(member.constructorBodyReference);
-        }
-      }
-    }
-
-    for (final lib in translator.libraries) {
-      for (final member in lib.members) {
-        if (!member.isDynamicModuleCallable(translator.coreTypes)) continue;
-        collectCallableReferences(member);
-      }
-
-      for (final cls in lib.classes) {
-        for (final member in cls.members) {
-          if (!member.isDynamicModuleCallable(translator.coreTypes)) continue;
-          collectCallableReferences(member);
-        }
-      }
-    }
-
-    return exports;
-  }
-
   w.BaseFunction? getExistingFunction(Reference target) {
     return _functions[target];
   }
@@ -261,8 +159,8 @@ class FunctionCollector {
       // Export the function from the main module if it is callable from dynamic
       // modules.
       if (translator.dynamicModuleSupportEnabled &&
-          dynamicModuleCallable.contains(target)) {
-        assert(translator.dynamicModuleSupportEnabled);
+          translator.dynamicModuleInfo!.metadata.callableReferences
+              .contains(target)) {
         _importedDynamicModuleFunctions.get(function, translator.dynamicModule,
             exportOnly: true);
       }
@@ -377,7 +275,7 @@ class FunctionCollector {
           .targets(unchecked: useUncheckedEntry, dynamicModule: false)
           .targetRanges) {
         for (int classId = range.start; classId <= range.end; ++classId) {
-          _recordClassTargetUse(classId, target);
+          recordClassTargetUse(classId, target);
         }
       }
 
@@ -386,14 +284,14 @@ class FunctionCollector {
             .targets(unchecked: useUncheckedEntry, dynamicModule: true)
             .targetRanges) {
           for (int classId = range.start; classId <= range.end; ++classId) {
-            _recordClassTargetUse(classId, target);
+            recordClassTargetUse(classId, target);
           }
         }
       }
     }
   }
 
-  void _recordClassTargetUse(int classId, Reference target) {
+  void recordClassTargetUse(int classId, Reference target) {
     if (_allocatedClasses.contains(classId)) {
       // Class declaring or inheriting member is allocated somewhere.
       getFunction(target);
diff --git a/pkg/dart2wasm/lib/serialization.dart b/pkg/dart2wasm/lib/serialization.dart
index d124d5067ff..fb98f59662a 100644
--- a/pkg/dart2wasm/lib/serialization.dart
+++ b/pkg/dart2wasm/lib/serialization.dart
@@ -5,13 +5,193 @@
 import 'dart:convert';
 import 'dart:typed_data';
 
-class BinaryDataSink {
+import 'package:kernel/ast.dart';
+
+import 'dynamic_module_kernel_metadata.dart';
+import 'reference_extensions.dart';
+
+class _EntityToIdMapper {
+  final Component component;
+  final Map<TreeNode, int> _ids;
+
+  _EntityToIdMapper(this.component)
+      : _ids =
+            (component.metadata[DynamicModuleGlobalIdRepository.repositoryTag]
+                    as DynamicModuleGlobalIdRepository)
+                .mapping;
+
+  int idForClass(Class cls) {
+    return _ids[cls]!;
+  }
+
+  int? idForMember(Member member) {
+    return _ids[member];
+  }
+
+  (int, int)? idForReference(Reference reference) {
+    final memberId = idForMember(reference.asMember);
+    if (memberId == null) return null;
+    return (memberId, _flagForReference(reference));
+  }
+
+  static int _flagForReference(Reference reference) {
+    if (reference.isImplicitGetter) return 0;
+    if (reference.isImplicitSetter) return 1;
+    if (reference.isTearOffReference) return 2;
+    if (reference.isConstructorBodyReference) return 3;
+    if (reference.isInitializerReference) return 4;
+    if (reference.isTypeCheckerReference) return 5;
+    if (reference.isCheckedEntryReference) return 6;
+    if (reference.isUncheckedEntryReference) return 7;
+    if (reference.isBodyReference) return 8;
+    assert(reference == reference.asMember.reference);
+    return 9;
+  }
+}
+
+class _IdToEntityMapper {
+  final Component component;
+  final Map<int, TreeNode> _mapping;
+
+  static Map<int, TreeNode> _makeIdsMap(Component component) {
+    final mapping =
+        (component.metadata[DynamicModuleGlobalIdRepository.repositoryTag]
+                as DynamicModuleGlobalIdRepository)
+            .mapping;
+    final inverse = <int, TreeNode>{};
+    mapping.forEach((node, id) {
+      inverse[id] = node;
+    });
+    return inverse;
+  }
+
+  _IdToEntityMapper(this.component) : _mapping = _makeIdsMap(component);
+
+  Class classForId(int id) {
+    return _mapping[id] as Class;
+  }
+
+  Member memberForId(int id) {
+    return _mapping[id] as Member;
+  }
+
+  Reference referenceForId(int classId, int flag) {
+    final member = _mapping[classId] as Member;
+    return _referenceForFlag(member, flag);
+  }
+
+  static Reference _referenceForFlag(Member member, int flag) {
+    if (flag == 0) return (member as Field).getterReference;
+    if (flag == 1) return (member as Field).setterReference!;
+    if (flag == 2) return (member as Procedure).tearOffReference;
+    if (flag == 3) return (member as Constructor).constructorBodyReference;
+    if (flag == 4) return (member as Constructor).initializerReference;
+    if (flag == 5) return member.typeCheckerReference;
+    if (flag == 6) return member.checkedEntryReference;
+    if (flag == 7) return member.uncheckedEntryReference;
+    if (flag == 8) return member.bodyReference;
+    assert(flag == 9);
+    return member.reference;
+  }
+}
+
+class DataSerializer {
+  final _BinaryDataSink _sink = _BinaryDataSink();
+  final _EntityToIdMapper _mapper;
+
+  DataSerializer(Component component) : _mapper = _EntityToIdMapper(component);
+
+  void writeString(String value) {
+    _sink.writeString(value);
+  }
+
+  void writeInt(int value) {
+    _sink.writeInt(value);
+  }
+
+  void writeBool(bool value) {
+    _sink.writeInt(value ? 1 : 0);
+  }
+
+  void writeEnum<E extends Enum>(E value) {
+    writeInt(value.index);
+  }
+
+  void writeClass(Class cls) {
+    writeInt(_mapper.idForClass(cls));
+  }
+
+  bool writeMember(Member member) {
+    final memberId = _mapper.idForMember(member);
+    if (memberId == null) return false;
+    writeInt(memberId);
+    return true;
+  }
+
+  bool writeReference(Reference reference) {
+    final referenceId = _mapper.idForReference(reference);
+    if (referenceId == null) return false;
+    writeInt(referenceId.$1);
+    writeInt(referenceId.$2);
+    return true;
+  }
+
+  Uint8List takeBytes() {
+    return _sink.takeBytes();
+  }
+}
+
+class DataDeserializer {
+  final _BinaryDataSource _source;
+  final _IdToEntityMapper _mapper;
+
+  DataDeserializer(Uint8List bytes, Component component)
+      : _source = _BinaryDataSource(bytes),
+        _mapper = _IdToEntityMapper(component);
+
+  String readString() {
+    return _source.readString();
+  }
+
+  int readInt() {
+    return _source.readInt();
+  }
+
+  bool readBool() {
+    return _source.readInt() == 1;
+  }
+
+  E readEnum<E extends Enum>(List<E> values) {
+    int index = _source.readInt();
+    assert(
+        0 <= index && index < values.length,
+        "Invalid data kind index. "
+        "Expected one of $values, found index $index.");
+    return values[index];
+  }
+
+  Class readClass() {
+    return _mapper.classForId(_source.readInt());
+  }
+
+  Member readMember() {
+    return _mapper.memberForId(_source.readInt());
+  }
+
+  Reference readReference() {
+    final classId = _source.readInt();
+    final flag = _source.readInt();
+    return _mapper.referenceForId(classId, flag);
+  }
+}
+
+class _BinaryDataSink {
   static const int _initSinkSize = 50 * 1024;
 
   Uint8List _data = Uint8List(_initSinkSize);
   int _length = 0;
 
-  BinaryDataSink();
+  _BinaryDataSink();
 
   int get length => _length;
 
@@ -62,15 +242,6 @@ class BinaryDataSink {
     }
   }
 
-  void writeClassId(int value) {
-    // Add 1 since some class IDs are -1.
-    writeInt(value + 1);
-  }
-
-  void writeEnum<E extends Enum>(E value) {
-    writeInt(value.index);
-  }
-
   Uint8List takeBytes() {
     final result = Uint8List.sublistView(_data, 0, _length);
     // Free the reference to the large data list so it can potentially be
@@ -80,11 +251,11 @@ class BinaryDataSink {
   }
 }
 
-class BinaryDataSource {
+class _BinaryDataSource {
   int _byteOffset = 0;
   final Uint8List _bytes;
 
-  BinaryDataSource(this._bytes);
+  _BinaryDataSource(this._bytes);
 
   void begin(String tag) {}
 
@@ -119,20 +290,6 @@ class BinaryDataSource {
     }
   }
 
-  int readClassId() {
-    // Subtract 1 since some class IDs are -1.
-    return readInt() - 1;
-  }
-
-  E readEnum<E extends Enum>(List<E> values) {
-    int index = readInt();
-    assert(
-        0 <= index && index < values.length,
-        "Invalid data kind index. "
-        "Expected one of $values, found index $index.");
-    return values[index];
-  }
-
   int get length => _bytes.length;
   int get currentOffset => _byteOffset;
 }
diff --git a/pkg/dart2wasm/lib/translator.dart b/pkg/dart2wasm/lib/translator.dart
index c1317ccf158..dfd91490379 100644
--- a/pkg/dart2wasm/lib/translator.dart
+++ b/pkg/dart2wasm/lib/translator.dart
@@ -61,7 +61,7 @@ class TranslatorOptions {
   bool requireJsStringBuiltin = false;
   List<int> watchPoints = [];
 
-  void serialize(BinaryDataSink sink) {
+  void serialize(DataSerializer sink) {
     sink.writeBool(enableAsserts);
     sink.writeBool(importSharedMemory);
     sink.writeBool(inlining);
@@ -85,7 +85,7 @@ class TranslatorOptions {
         sharedMemoryMaxPages == null ? 0 : (sharedMemoryMaxPages! + 1));
   }
 
-  static TranslatorOptions deserialize(BinaryDataSource source) {
+  static TranslatorOptions deserialize(DataDeserializer source) {
     final TranslatorOptions options = TranslatorOptions();
     options.enableAsserts = source.readBool();
     options.importSharedMemory = source.readBool();
@@ -410,7 +410,7 @@ class Translator with KernelNodes {
   Translator(this.component, this.coreTypes, this.index, this.recordClasses,
       this._moduleOutputData, this.options,
       {bool enableDynamicModules = false,
-      DynamicModuleMetadata? dynamicModuleMetadata})
+      required MainModuleMetadata mainModuleMetadata})
       : libraries = component.libraries,
         hierarchy =
             ClassHierarchy(component, coreTypes) as ClosedWorldClassHierarchy {
@@ -425,7 +425,7 @@ class Translator with KernelNodes {
     types = Types(this);
     exceptionTag = ExceptionTag(this);
     if (enableDynamicModules) {
-      dynamicModuleInfo = DynamicModuleInfo(this, dynamicModuleMetadata);
+      dynamicModuleInfo = DynamicModuleInfo(this, mainModuleMetadata);
     }
   }
 
diff --git a/pkg/wasm_builder/lib/src/builder/types.dart b/pkg/wasm_builder/lib/src/builder/types.dart
index 94ce6d5cacd..174ada40a45 100644
--- a/pkg/wasm_builder/lib/src/builder/types.dart
+++ b/pkg/wasm_builder/lib/src/builder/types.dart
@@ -75,6 +75,7 @@ class _RecGroupBuilder {
   late final List<List<ir.DefType>> _allRecursiveGroups =
       _createAllRecursiveGroups();
   final List<ir.DefType> _allDefinedTypes = [];
+  final Map<ir.DefType, int> _brandTypeAssignments = {};
 
   _RecGroupBuilder();
 
@@ -121,7 +122,7 @@ class _RecGroupBuilder {
   /// If a rec group is in an equivalence class with multiple groups, it will be
   /// assigned an index encoded as a brand type. The brand types allows the wasm
   /// type system to disambiguate members of otherwise equivalent rec groups.
-  static void _assignBrandTypes(List<List<ir.DefType>> groups) {
+  void _assignBrandTypes(List<List<ir.DefType>> groups) {
     // Collect rec groups joining over:
     // (1) group length
     // (2) length of first struct
@@ -148,7 +149,12 @@ class _RecGroupBuilder {
       // All the groups in `equalGroups` are structurally equivalent.
       // Skip the first group since we can leave one group as-is.
       for (int i = 1; i < equalGroups.length; i++) {
-        equalGroups[i].insert(0, _getBrandType(i - 1));
+        // Key the assignment on the first element in the group. If a user is
+        // trying to use the brand index to restore the group, then all other
+        // elements are implicitly the same.
+        final typeIndex = _brandTypeAssignments[equalGroups[i].first] ??= i - 1;
+        final brandType = _getBrandType(typeIndex);
+        equalGroups[i].insert(0, brandType);
       }
     }
   }
@@ -241,6 +247,12 @@ class TypesBuilder with Builder<ir.Types> {
   TypesBuilder(this._module, {TypesBuilder? parent})
       : _recGroupBuilder = parent?._recGroupBuilder ?? _RecGroupBuilder();
 
+  Map<ir.DefType, int> get brandTypeAssignments =>
+      _recGroupBuilder._brandTypeAssignments;
+
+  void addBrandTypeAssignment(ir.DefType type, int brandIndex) =>
+      _recGroupBuilder._brandTypeAssignments[type] = brandIndex;
+
   /// Add a new function type to the module.
   ///
   /// All function types are canonicalized, such that identical types become