diff --git a/pkg/front_end/lib/src/builder/formal_parameter_builder.dart b/pkg/front_end/lib/src/builder/formal_parameter_builder.dart
index 52ec83a94d4..0adfbd9b887 100644
--- a/pkg/front_end/lib/src/builder/formal_parameter_builder.dart
+++ b/pkg/front_end/lib/src/builder/formal_parameter_builder.dart
@@ -22,7 +22,7 @@ import '../kernel/body_builder.dart' show BodyBuilder;
 import '../kernel/body_builder_context.dart';
 import '../kernel/internal_ast.dart' show VariableDeclarationImpl;
 import '../kernel/wildcard_lowering.dart';
-import '../source/builder_factory.dart';
+import '../source/fragment_factory.dart';
 import '../source/source_constructor_builder.dart';
 import '../source/source_factory_builder.dart';
 import '../source/source_library_builder.dart';
@@ -192,7 +192,7 @@ class FormalParameterBuilder extends NamedBuilderImpl
     }
   }
 
-  FormalParameterBuilder forPrimaryConstructor(BuilderFactory builderFactory) {
+  FormalParameterBuilder forPrimaryConstructor(FragmentFactory builderFactory) {
     return new FormalParameterBuilder(
         kind,
         modifiers | Modifiers.InitializingFormal,
diff --git a/pkg/front_end/lib/src/fragment/constructor/encoding.dart b/pkg/front_end/lib/src/fragment/constructor/encoding.dart
index 02aabb0a285..e61ecb0b041 100644
--- a/pkg/front_end/lib/src/fragment/constructor/encoding.dart
+++ b/pkg/front_end/lib/src/fragment/constructor/encoding.dart
@@ -17,7 +17,7 @@ import '../../kernel/body_builder_context.dart';
 import '../../kernel/constructor_tearoff_lowering.dart';
 import '../../kernel/internal_ast.dart';
 import '../../kernel/kernel_helper.dart';
-import '../../source/builder_factory.dart';
+import '../../source/fragment_factory.dart';
 import '../../source/name_scheme.dart';
 import '../../source/source_class_builder.dart';
 import '../../source/source_constructor_builder.dart';
diff --git a/pkg/front_end/lib/src/fragment/factory/encoding.dart b/pkg/front_end/lib/src/fragment/factory/encoding.dart
index d145bcc52b3..14393c37a73 100644
--- a/pkg/front_end/lib/src/fragment/factory/encoding.dart
+++ b/pkg/front_end/lib/src/fragment/factory/encoding.dart
@@ -28,7 +28,7 @@ import '../../fragment/fragment.dart';
 import '../../kernel/body_builder_context.dart';
 import '../../kernel/constructor_tearoff_lowering.dart';
 import '../../kernel/kernel_helper.dart';
-import '../../source/builder_factory.dart';
+import '../../source/fragment_factory.dart';
 import '../../source/name_scheme.dart';
 import '../../source/redirecting_factory_body.dart';
 import '../../source/source_factory_builder.dart';
diff --git a/pkg/front_end/lib/src/fragment/fragment.dart b/pkg/front_end/lib/src/fragment/fragment.dart
index b07923b301e..829ef64ccdd 100644
--- a/pkg/front_end/lib/src/fragment/fragment.dart
+++ b/pkg/front_end/lib/src/fragment/fragment.dart
@@ -42,7 +42,7 @@ import '../kernel/internal_ast.dart';
 import '../kernel/late_lowering.dart' as late_lowering;
 import '../kernel/member_covariance.dart';
 import '../kernel/type_algorithms.dart';
-import '../source/builder_factory.dart';
+import '../source/fragment_factory.dart';
 import '../source/name_scheme.dart';
 import '../source/source_class_builder.dart';
 import '../source/source_constructor_builder.dart';
diff --git a/pkg/front_end/lib/src/fragment/method/encoding.dart b/pkg/front_end/lib/src/fragment/method/encoding.dart
index ddeacaf7c4c..823f438b732 100644
--- a/pkg/front_end/lib/src/fragment/method/encoding.dart
+++ b/pkg/front_end/lib/src/fragment/method/encoding.dart
@@ -16,7 +16,7 @@ import '../../builder/type_builder.dart';
 import '../../builder/variable_builder.dart';
 import '../../kernel/body_builder_context.dart';
 import '../../kernel/type_algorithms.dart';
-import '../../source/builder_factory.dart';
+import '../../source/fragment_factory.dart';
 import '../../source/name_scheme.dart';
 import '../../source/source_class_builder.dart';
 import '../../source/source_function_builder.dart';
diff --git a/pkg/front_end/lib/src/kernel/utils.dart b/pkg/front_end/lib/src/kernel/utils.dart
index 928a2138205..8513507d3a4 100644
--- a/pkg/front_end/lib/src/kernel/utils.dart
+++ b/pkg/front_end/lib/src/kernel/utils.dart
@@ -29,7 +29,7 @@ import '../builder/omitted_type_builder.dart';
 import '../builder/record_type_builder.dart';
 import '../builder/type_builder.dart';
 import '../fragment/fragment.dart';
-import '../source/builder_factory.dart';
+import '../source/fragment_factory.dart';
 import '../source/source_type_parameter_builder.dart';
 import 'body_builder.dart';
 
diff --git a/pkg/front_end/lib/src/source/builder_factory.dart b/pkg/front_end/lib/src/source/fragment_factory.dart
similarity index 99%
rename from pkg/front_end/lib/src/source/builder_factory.dart
rename to pkg/front_end/lib/src/source/fragment_factory.dart
index 3a2a7051345..c81ab5b180a 100644
--- a/pkg/front_end/lib/src/source/builder_factory.dart
+++ b/pkg/front_end/lib/src/source/fragment_factory.dart
@@ -30,7 +30,7 @@ import 'source_library_builder.dart';
 import 'source_type_parameter_builder.dart';
 import 'type_parameter_scope_builder.dart';
 
-abstract class BuilderFactoryResult {
+abstract class FragmentFactoryResult {
   String? get name;
 
   bool get isPart;
@@ -67,7 +67,7 @@ abstract class BuilderFactoryResult {
   List<LibraryPart> get libraryParts;
 }
 
-abstract class BuilderFactory {
+abstract class FragmentFactory {
   void beginClassOrNamedMixinApplicationHeader();
 
   /// Registers that this builder is preparing for a class declaration with the
diff --git a/pkg/front_end/lib/src/source/source_builder_factory.dart b/pkg/front_end/lib/src/source/fragment_factory_impl.dart
similarity index 99%
rename from pkg/front_end/lib/src/source/source_builder_factory.dart
rename to pkg/front_end/lib/src/source/fragment_factory_impl.dart
index e90bbf9ff8e..3f740468f4c 100644
--- a/pkg/front_end/lib/src/source/source_builder_factory.dart
+++ b/pkg/front_end/lib/src/source/fragment_factory_impl.dart
@@ -36,7 +36,7 @@ import '../builder/type_builder.dart';
 import '../builder/void_type_builder.dart';
 import '../fragment/fragment.dart';
 import '../util/local_stack.dart';
-import 'builder_factory.dart';
+import 'fragment_factory.dart';
 import 'offset_map.dart';
 import 'source_class_builder.dart' show SourceClassBuilder;
 import 'source_library_builder.dart';
@@ -44,7 +44,7 @@ import 'source_loader.dart' show SourceLoader;
 import 'source_type_parameter_builder.dart';
 import 'type_parameter_scope_builder.dart';
 
-class BuilderFactoryImpl implements BuilderFactory, BuilderFactoryResult {
+class FragmentFactoryImpl implements FragmentFactory, FragmentFactoryResult {
   final SourceCompilationUnit _compilationUnit;
 
   final ProblemReporting _problemReporting;
@@ -113,7 +113,7 @@ class BuilderFactoryImpl implements BuilderFactory, BuilderFactoryResult {
   final LocalStack<DeclarationFragmentImpl> _declarationFragments =
       new LocalStack([]);
 
-  BuilderFactoryImpl(
+  FragmentFactoryImpl(
       {required SourceCompilationUnit compilationUnit,
       required SourceCompilationUnit augmentationRoot,
       required LibraryNameSpaceBuilder libraryNameSpaceBuilder,
diff --git a/pkg/front_end/lib/src/source/outline_builder.dart b/pkg/front_end/lib/src/source/outline_builder.dart
index 9db2783ad8c..896b15525d2 100644
--- a/pkg/front_end/lib/src/source/outline_builder.dart
+++ b/pkg/front_end/lib/src/source/outline_builder.dart
@@ -49,7 +49,7 @@ import '../builder/record_type_builder.dart';
 import '../builder/type_builder.dart';
 import '../fragment/fragment.dart';
 import '../kernel/utils.dart';
-import 'builder_factory.dart';
+import 'fragment_factory.dart';
 import 'offset_map.dart';
 import 'source_type_parameter_builder.dart';
 import 'stack_listener_impl.dart';
@@ -477,7 +477,7 @@ extension on DeclarationContext {
 
 class OutlineBuilder extends StackListenerImpl {
   final SourceCompilationUnit _compilationUnit;
-  final BuilderFactory _builderFactory;
+  final FragmentFactory _builderFactory;
 
   final bool enableNative;
   bool inAbstractOrSealedClass = false;
diff --git a/pkg/front_end/lib/src/source/source_class_builder.dart b/pkg/front_end/lib/src/source/source_class_builder.dart
index 8322bfd94cb..451909d162d 100644
--- a/pkg/front_end/lib/src/source/source_class_builder.dart
+++ b/pkg/front_end/lib/src/source/source_class_builder.dart
@@ -47,7 +47,7 @@ import '../kernel/hierarchy/hierarchy_node.dart';
 import '../kernel/kernel_helper.dart';
 import '../kernel/type_algorithms.dart';
 import '../kernel/utils.dart' show compareProcedures;
-import 'builder_factory.dart';
+import 'fragment_factory.dart';
 import 'class_declaration.dart';
 import 'name_scheme.dart';
 import 'source_builder_mixins.dart';
diff --git a/pkg/front_end/lib/src/source/source_compilation_unit.dart b/pkg/front_end/lib/src/source/source_compilation_unit.dart
index 5fbf7d73a17..b001c272eef 100644
--- a/pkg/front_end/lib/src/source/source_compilation_unit.dart
+++ b/pkg/front_end/lib/src/source/source_compilation_unit.dart
@@ -87,9 +87,9 @@ class SourceCompilationUnitImpl implements SourceCompilationUnit {
   @override
   final IndexedLibrary? indexedLibrary;
 
-  late final BuilderFactoryImpl _builderFactory;
+  late final FragmentFactoryImpl _fragmentFactory;
 
-  late final BuilderFactoryResult _builderFactoryResult;
+  late final FragmentFactoryResult _fragmentFactoryResult;
 
   final LibraryNameSpaceBuilder _libraryNameSpaceBuilder;
 
@@ -208,7 +208,7 @@ class SourceCompilationUnitImpl implements SourceCompilationUnit {
         parent: libraryScope);
 
     // TODO(johnniwinther): Create these in [createOutlineBuilder].
-    _builderFactoryResult = _builderFactory = new BuilderFactoryImpl(
+    _fragmentFactoryResult = _fragmentFactory = new FragmentFactoryImpl(
         compilationUnit: this,
         augmentationRoot: augmentationRoot ?? this,
         libraryNameSpaceBuilder: libraryNameSpaceBuilder,
@@ -434,10 +434,10 @@ class SourceCompilationUnitImpl implements SourceCompilationUnit {
 
   @override
   Iterable<Uri> get dependencies sync* {
-    for (Export export in _builderFactoryResult.exports) {
+    for (Export export in _fragmentFactoryResult.exports) {
       yield export.exportedCompilationUnit.importUri;
     }
-    for (Import import in _builderFactoryResult.imports) {
+    for (Import import in _fragmentFactoryResult.imports) {
       CompilationUnit? imported = import.importedCompilationUnit;
       if (imported != null) {
         yield imported.importUri;
@@ -446,7 +446,7 @@ class SourceCompilationUnitImpl implements SourceCompilationUnit {
   }
 
   @override
-  bool get isPart => _builderFactoryResult.isPart;
+  bool get isPart => _fragmentFactoryResult.isPart;
 
   @override
   bool get isSynthetic => accessProblem != null;
@@ -468,7 +468,7 @@ class SourceCompilationUnitImpl implements SourceCompilationUnit {
   OutlineBuilder createOutlineBuilder() {
     assert(_offsetMap == null, "OffsetMap has already been set for $this");
     return new OutlineBuilder(
-        this, _builderFactory, _offsetMap = new OffsetMap(fileUri));
+        this, _fragmentFactory, _offsetMap = new OffsetMap(fileUri));
   }
 
   @override
@@ -538,7 +538,7 @@ class SourceCompilationUnitImpl implements SourceCompilationUnit {
       return;
     }
 
-    for (Import import in _builderFactoryResult.imports) {
+    for (Import import in _fragmentFactoryResult.imports) {
       // Rather than add a LibraryDependency, we attach an annotation.
       if (import.nativeImportPath != null) {
         _addNativeDependency(library, import.nativeImportPath!);
@@ -559,7 +559,7 @@ class SourceCompilationUnitImpl implements SourceCompilationUnit {
       library.addDependency(libraryDependency);
       import.libraryDependency = libraryDependency;
     }
-    for (Export export in _builderFactoryResult.exports) {
+    for (Export export in _fragmentFactoryResult.exports) {
       LibraryDependency libraryDependency = new LibraryDependency.export(
           export.exportedLibraryBuilder.library,
           combinators: toCombinators(export.combinators))
@@ -570,10 +570,10 @@ class SourceCompilationUnitImpl implements SourceCompilationUnit {
   }
 
   @override
-  String? get partOfName => _builderFactoryResult.partOfName;
+  String? get partOfName => _fragmentFactoryResult.partOfName;
 
   @override
-  Uri? get partOfUri => _builderFactoryResult.partOfUri;
+  Uri? get partOfUri => _fragmentFactoryResult.partOfUri;
 
   @override
   LookupScope get compilationUnitScope => _compilationUnitScope;
@@ -590,7 +590,7 @@ class SourceCompilationUnitImpl implements SourceCompilationUnit {
   @override
   void takeMixinApplications(
       Map<SourceClassBuilder, TypeBuilder> mixinApplications) {
-    _builderFactoryResult.takeMixinApplications(mixinApplications);
+    _fragmentFactoryResult.takeMixinApplications(mixinApplications);
   }
 
   @override
@@ -609,7 +609,7 @@ class SourceCompilationUnitImpl implements SourceCompilationUnit {
       required List<SourceCompilationUnit> includedParts,
       required Set<Uri> usedParts}) {
     Set<Uri> seenParts = new Set<Uri>();
-    for (Part part in _builderFactoryResult.parts) {
+    for (Part part in _fragmentFactoryResult.parts) {
       // TODO(johnniwinther): Use [part.offset] in messages.
       if (part.compilationUnit == this) {
         addProblem(messagePartOfSelf, -1, noLength, fileUri);
@@ -819,17 +819,17 @@ class SourceCompilationUnitImpl implements SourceCompilationUnit {
 
   @override
   int resolveTypes(ProblemReporting problemReporting) {
-    return _builderFactoryResult.typeScope.resolveTypes(problemReporting);
+    return _fragmentFactoryResult.typeScope.resolveTypes(problemReporting);
   }
 
   @override
   int finishNativeMethods() {
-    return _builderFactoryResult.finishNativeMethods();
+    return _fragmentFactoryResult.finishNativeMethods();
   }
 
   void _clearPartsAndReportExporters() {
     assert(_libraryBuilder != null, "Library has not be set.");
-    _builderFactoryResult.parts.clear();
+    _fragmentFactoryResult.parts.clear();
     if (exporters.isNotEmpty) {
       // Coverage-ignore-block(suite): Not run.
       List<LocatedMessage> context = <LocatedMessage>[
@@ -859,12 +859,12 @@ class SourceCompilationUnitImpl implements SourceCompilationUnit {
     _partOfLibrary = libraryBuilder;
     _parentCompilationUnit = parentCompilationUnit;
     if (!allowPartInParts) {
-      if (_builderFactoryResult.parts.isNotEmpty) {
+      if (_fragmentFactoryResult.parts.isNotEmpty) {
         List<LocatedMessage> context = <LocatedMessage>[
           messagePartInPartLibraryContext.withLocation(
               libraryBuilder.fileUri, -1, 1),
         ];
-        for (Part part in _builderFactoryResult.parts) {
+        for (Part part in _fragmentFactoryResult.parts) {
           addProblem(messagePartInPart, part.fileOffset, noLength, fileUri,
               context: context);
           // Mark this part as used so we don't report it as orphaned.
@@ -903,7 +903,7 @@ class SourceCompilationUnitImpl implements SourceCompilationUnit {
       Map<NominalParameterBuilder, SourceLibraryBuilder> nominalVariables,
       Map<StructuralParameterBuilder, SourceLibraryBuilder>
           structuralVariables) {
-    _builderFactoryResult.collectUnboundTypeParameters(
+    _fragmentFactoryResult.collectUnboundTypeParameters(
         libraryBuilder, nominalVariables, structuralVariables);
   }
 
@@ -916,7 +916,7 @@ class SourceCompilationUnitImpl implements SourceCompilationUnit {
       required bool deferred}) {
     assert(
         checkState(pending: [SourceCompilationUnitState.importsAddedToScope]));
-    _builderFactory.addImport(
+    _fragmentFactory.addImport(
         metadata: null,
         isAugmentationImport: false,
         uri: uri,
@@ -936,7 +936,7 @@ class SourceCompilationUnitImpl implements SourceCompilationUnit {
     bool hasCoreImport = originImportUri == dartCore &&
         // Coverage-ignore(suite): Not run.
         !forPatchLibrary;
-    for (Import import in _builderFactoryResult.imports) {
+    for (Import import in _fragmentFactoryResult.imports) {
       if (import.importedCompilationUnit?.isPart ?? false) {
         // Coverage-ignore-block(suite): Not run.
         addProblem(
@@ -998,7 +998,7 @@ class SourceCompilationUnitImpl implements SourceCompilationUnit {
 
   @override
   void buildOutlineNode(Library library) {
-    for (LibraryPart libraryPart in _builderFactoryResult.libraryParts) {
+    for (LibraryPart libraryPart in _fragmentFactoryResult.libraryParts) {
       library.addPart(libraryPart);
     }
   }
@@ -1009,7 +1009,7 @@ class SourceCompilationUnitImpl implements SourceCompilationUnit {
         checkState(required: [SourceCompilationUnitState.importsAddedToScope]));
 
     int total = 0;
-    for (Import import in _builderFactoryResult.imports) {
+    for (Import import in _fragmentFactoryResult.imports) {
       if (import.deferred) {
         Procedure? tearoff =
             import.prefixFragment!.builder.loadLibraryBuilder?.tearoff;
@@ -1026,10 +1026,10 @@ class SourceCompilationUnitImpl implements SourceCompilationUnit {
   }
 
   @override
-  List<MetadataBuilder>? get metadata => _builderFactoryResult.metadata;
+  List<MetadataBuilder>? get metadata => _fragmentFactoryResult.metadata;
 
   @override
-  String? get name => _builderFactoryResult.name;
+  String? get name => _fragmentFactoryResult.name;
 
   @override
   int computeDefaultTypes(TypeBuilder dynamicType, TypeBuilder nullType,
@@ -1062,7 +1062,7 @@ class SourceCompilationUnitImpl implements SourceCompilationUnit {
       }
     }
 
-    _builderFactoryResult
+    _fragmentFactoryResult
         .registerUnresolvedStructuralParameters(unboundTypeParameters);
 
     return count;
diff --git a/pkg/front_end/lib/src/source/source_library_builder.dart b/pkg/front_end/lib/src/source/source_library_builder.dart
index 4b04c3e73b2..346dc36bc3d 100644
--- a/pkg/front_end/lib/src/source/source_library_builder.dart
+++ b/pkg/front_end/lib/src/source/source_library_builder.dart
@@ -58,12 +58,12 @@ import '../kernel/utils.dart'
         exportNeverSentinel,
         toCombinators,
         unserializableExportName;
-import 'builder_factory.dart';
 import 'class_declaration.dart';
+import 'fragment_factory.dart';
+import 'fragment_factory_impl.dart';
 import 'name_scheme.dart';
 import 'offset_map.dart';
 import 'outline_builder.dart';
-import 'source_builder_factory.dart';
 import 'source_builder_mixins.dart';
 import 'source_class_builder.dart' show SourceClassBuilder;
 import 'source_extension_builder.dart';
diff --git a/pkg/front_end/test/coverage_suite_expected.dart b/pkg/front_end/test/coverage_suite_expected.dart
index 0824acbcb44..1994befd084 100644
--- a/pkg/front_end/test/coverage_suite_expected.dart
+++ b/pkg/front_end/test/coverage_suite_expected.dart
@@ -899,7 +899,7 @@ const Map<String, ({int hitCount, int missCount})> _expect = {
     missCount: 0,
   ),
   // 100.0%.
-  "package:front_end/src/source/builder_factory.dart": (
+  "package:front_end/src/source/fragment_factory.dart": (
     hitCount: 68,
     missCount: 0,
   ),
@@ -934,7 +934,7 @@ const Map<String, ({int hitCount, int missCount})> _expect = {
     missCount: 0,
   ),
   // 100.0%.
-  "package:front_end/src/source/source_builder_factory.dart": (
+  "package:front_end/src/source/source_fragment_factory.dart": (
     hitCount: 1159,
     missCount: 0,
   ),