diff --git a/dwds/lib/src/debugging/chrome_inspector.dart b/dwds/lib/src/debugging/chrome_inspector.dart
new file mode 100644
index 000000000..e3cac4848
--- /dev/null
+++ b/dwds/lib/src/debugging/chrome_inspector.dart
@@ -0,0 +1,679 @@
+// Copyright (c) 2019, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'dart:math' as math;
+
+import 'package:dwds/src/config/tool_configuration.dart';
+import 'package:dwds/src/connections/app_connection.dart';
+import 'package:dwds/src/debugging/classes.dart';
+import 'package:dwds/src/debugging/debugger.dart';
+import 'package:dwds/src/debugging/execution_context.dart';
+import 'package:dwds/src/debugging/inspector.dart';
+import 'package:dwds/src/debugging/instance.dart';
+import 'package:dwds/src/debugging/libraries.dart';
+import 'package:dwds/src/debugging/location.dart';
+import 'package:dwds/src/debugging/metadata/provider.dart';
+import 'package:dwds/src/debugging/remote_debugger.dart';
+import 'package:dwds/src/loaders/ddc_library_bundle.dart';
+import 'package:dwds/src/readers/asset_reader.dart';
+import 'package:dwds/src/utilities/conversions.dart';
+import 'package:dwds/src/utilities/dart_uri.dart';
+import 'package:dwds/src/utilities/domain.dart';
+import 'package:dwds/src/utilities/objects.dart';
+import 'package:dwds/src/utilities/server.dart';
+import 'package:dwds/src/utilities/shared.dart';
+import 'package:logging/logging.dart';
+import 'package:meta/meta.dart';
+import 'package:vm_service/vm_service.dart';
+import 'package:webkit_inspection_protocol/webkit_inspection_protocol.dart';
+
+/// An inspector for a running Dart application contained in the
+/// [WipConnection].
+///
+/// Provides information about currently loaded scripts and objects and support
+/// for eval.
+class ChromeAppInspector extends AppInspector {
+  final _logger = Logger('AppInspector');
+
+  final RemoteDebugger remoteDebugger;
+  final ExecutionContext _executionContext;
+
+  @override
+  @protected
+  late final ChromeLibraryHelper libraryHelper = ChromeLibraryHelper(this);
+
+  late ChromeAppClassHelper _classHelper;
+  late ChromeAppInstanceHelper _instanceHelper;
+
+  final AssetReader _assetReader;
+  final Locations _locations;
+
+  /// JavaScript expression that evaluates to the Dart stack trace mapper.
+  static const stackTraceMapperExpression = '\$dartStackTraceUtility.mapper';
+
+  /// Regex used to extract the message from an exception description.
+  static final exceptionMessageRegex = RegExp(r'^.*$', multiLine: true);
+
+  /// Regex used to extract a stack trace line from the exception description.
+  static final stackTraceLineRegex = RegExp(r'^\s*at\s.*$', multiLine: true);
+
+  ChromeAppInspector._(
+    super.appConnection,
+    super.isolate,
+    this.remoteDebugger,
+    this._assetReader,
+    this._locations,
+    super.root,
+    this._executionContext,
+  );
+
+  /// Reset all caches and recompute any mappings.
+  ///
+  /// Should be called across hot reloads with a valid [ModifiedModuleReport].
+  @override
+  Future<void> initialize({ModifiedModuleReport? modifiedModuleReport}) async {
+    await super.initialize(modifiedModuleReport: modifiedModuleReport);
+
+    // TODO(srujzs): We can invalidate these in a smarter way instead of
+    // reinitializing when doing a hot reload, but these helpers recompute info
+    // on demand later and therefore are not in the critical path.
+    _classHelper = ChromeAppClassHelper(this);
+    _instanceHelper = ChromeAppInstanceHelper(this);
+  }
+
+  static Future<ChromeAppInspector> create(
+    AppConnection appConnection,
+    RemoteDebugger remoteDebugger,
+    AssetReader assetReader,
+    Locations locations,
+    String root,
+    Debugger debugger,
+    ExecutionContext executionContext,
+  ) async {
+    final id = createId();
+    final time = DateTime.now().millisecondsSinceEpoch;
+    final name = 'main()';
+    final isolate = Isolate(
+      id: id,
+      number: id,
+      name: name,
+      startTime: time,
+      runnable: true,
+      pauseOnExit: false,
+      pauseEvent: Event(
+        kind: EventKind.kPauseStart,
+        timestamp: time,
+        isolate: IsolateRef(
+          id: id,
+          name: name,
+          number: id,
+          isSystemIsolate: false,
+        ),
+      ),
+      livePorts: 0,
+      libraries: [],
+      breakpoints: [],
+      exceptionPauseMode: debugger.pauseState,
+      isSystemIsolate: false,
+      isolateFlags: [],
+    )..extensionRPCs = [];
+    final inspector = ChromeAppInspector._(
+      appConnection,
+      isolate,
+      remoteDebugger,
+      assetReader,
+      locations,
+      root,
+      executionContext,
+    );
+
+    debugger.updateInspector(inspector);
+    await inspector.initialize();
+    return inspector;
+  }
+
+  /// Returns the ID for the execution context or null if not found.
+  Future<int?> get contextId async {
+    try {
+      return await _executionContext.id;
+    } catch (e, s) {
+      _logger.severe('Missing execution context ID: ', e, s);
+      return null;
+    }
+  }
+
+  /// Get the value of the field named [fieldName] from [receiver].
+  Future<RemoteObject> loadField(RemoteObject receiver, String fieldName) {
+    final load = globalToolConfiguration.loadStrategy.dartRuntimeDebugger
+        .getPropertyJsExpression(fieldName);
+    return jsCallFunctionOn(receiver, load, []);
+  }
+
+  /// Call a method by name on [receiver], with arguments [positionalArgs] and
+  /// [namedArgs].
+  Future<RemoteObject> _invokeMethod(
+    RemoteObject receiver,
+    String methodName, [
+    List<RemoteObject> positionalArgs = const [],
+    Map namedArgs = const {},
+  ]) async {
+    // TODO(alanknight): Support named arguments.
+    if (namedArgs.isNotEmpty) {
+      throw UnsupportedError('Named arguments are not yet supported');
+    }
+    // We use the JS pseudo-variable 'arguments' to get the list of all arguments.
+    final send = globalToolConfiguration.loadStrategy.dartRuntimeDebugger
+        .callInstanceMethodJsExpression(methodName);
+    final remote = await jsCallFunctionOn(receiver, send, positionalArgs);
+    return remote;
+  }
+
+  /// Calls Chrome's Runtime.callFunctionOn method.
+  ///
+  /// [evalExpression] should be a JS function definition that can accept
+  /// [arguments].
+  Future<RemoteObject> jsCallFunctionOn(
+    RemoteObject receiver,
+    String evalExpression,
+    List<RemoteObject> arguments, {
+    bool returnByValue = false,
+  }) async {
+    final jsArguments = arguments.map(callArgumentFor).toList();
+    final response = await remoteDebugger.sendCommand(
+      'Runtime.callFunctionOn',
+      params: {
+        'functionDeclaration': evalExpression,
+        'arguments': jsArguments,
+        'objectId': receiver.objectId,
+        'returnByValue': returnByValue,
+      },
+    );
+    final result = getResultOrHandleError(
+      response,
+      evalContents: evalExpression,
+    );
+    return RemoteObject(result);
+  }
+
+  /// Calls Chrome's Runtime.callFunctionOn method with a global function.
+  ///
+  /// [evalExpression] should be a JS function definition that can accept
+  /// [arguments].
+  Future<RemoteObject> _jsCallFunction(
+    String evalExpression,
+    List<Object> arguments, {
+    bool returnByValue = false,
+  }) async {
+    final jsArguments = arguments.map(callArgumentFor).toList();
+    final response = await remoteDebugger.sendCommand(
+      'Runtime.callFunctionOn',
+      params: {
+        'functionDeclaration': evalExpression,
+        'arguments': jsArguments,
+        'executionContextId': await contextId,
+        'returnByValue': returnByValue,
+      },
+    );
+    final result = getResultOrHandleError(
+      response,
+      evalContents: evalExpression,
+    );
+    return RemoteObject(result);
+  }
+
+  /// Invoke the function named [selector] on the object identified by
+  /// [targetId].
+  ///
+  /// The [targetId] can be the URL of a Dart library, in which case this means
+  /// invoking a top-level function. The [arguments] are always strings that are
+  /// Dart object Ids (which can also be Chrome RemoteObject objectIds that are
+  /// for non-Dart JS objects.)
+  Future<RemoteObject> invoke(
+    String targetId,
+    String selector, [
+    List<dynamic> arguments = const [],
+  ]) async {
+    final remoteArguments = arguments
+        .cast<String>()
+        .map(remoteObjectFor)
+        .toList();
+    // We special case the Dart library, where invokeMethod won't work because
+    // it's not really a Dart object.
+    if (isLibraryId(targetId)) {
+      final library = await getObject(targetId) as Library;
+      return await _invokeLibraryFunction(library, selector, remoteArguments);
+    } else {
+      return _invokeMethod(
+        remoteObjectFor(targetId),
+        selector,
+        remoteArguments,
+      );
+    }
+  }
+
+  /// Invoke the function named [selector] from [library] with [arguments].
+  Future<RemoteObject> _invokeLibraryFunction(
+    Library library,
+    String selector,
+    List<RemoteObject> arguments,
+  ) {
+    final libraryUri = library.uri;
+    if (libraryUri == null) {
+      throwInvalidParam('invoke', 'library uri is null');
+    }
+    return globalToolConfiguration.loadStrategy is DdcLibraryBundleStrategy
+        ? _evaluateLibraryMethodWithDdcLibraryBundle(
+            libraryUri,
+            selector,
+            arguments,
+          )
+        : _evaluateInLibrary(
+            libraryUri,
+            'function () { return this.$selector.apply(this, arguments); }',
+            arguments,
+          );
+  }
+
+  /// Evaluate [expression] by calling Chrome's Runtime.evaluate.
+  Future<RemoteObject> jsEvaluate(
+    String expression, {
+    bool returnByValue = false,
+    bool awaitPromise = false,
+  }) async {
+    // TODO(alanknight): Support a version with arguments if needed.
+    final response = await remoteDebugger.sendCommand(
+      'Runtime.evaluate',
+      params: {
+        'expression': expression,
+        'returnByValue': returnByValue,
+        'awaitPromise': awaitPromise,
+        'contextId': await contextId,
+      },
+    );
+    final result = getResultOrHandleError(response, evalContents: expression);
+    return RemoteObject(result);
+  }
+
+  /// Evaluate the JS function with source [jsFunction] in the context of
+  /// the library identified by [libraryUri] with [arguments].
+  Future<RemoteObject> _evaluateInLibrary(
+    String libraryUri,
+    String jsFunction,
+    List<RemoteObject> arguments,
+  ) async {
+    final findLibraryJsExpression = globalToolConfiguration
+        .loadStrategy
+        .dartRuntimeDebugger
+        .callLibraryMethodJsExpression(libraryUri, jsFunction);
+
+    final remoteLibrary = await jsEvaluate(findLibraryJsExpression);
+    return jsCallFunctionOn(remoteLibrary, jsFunction, arguments);
+  }
+
+  /// Evaluates the specified top-level method [methodName] within the library
+  /// identified by [libraryUri] using the Dart Development Compiler (DDC)
+  /// library bundle strategy with the given optional [arguments].
+  Future<RemoteObject> _evaluateLibraryMethodWithDdcLibraryBundle(
+    String libraryUri,
+    String methodName, [
+    List<RemoteObject> arguments = const [],
+  ]) {
+    final expression = globalToolConfiguration.loadStrategy.dartRuntimeDebugger
+        .callLibraryMethodJsExpression(libraryUri, methodName);
+    return _jsCallFunction(expression, arguments);
+  }
+
+  /// Call [function] with objects referred by [argumentIds] as arguments.
+  Future<RemoteObject> callFunction(
+    String function,
+    Iterable<String> argumentIds,
+  ) {
+    final arguments = argumentIds.map(remoteObjectFor).toList();
+    return _jsCallFunction(function, arguments);
+  }
+
+  Future<InstanceRef?> instanceRefFor(Object value) =>
+      _instanceHelper.instanceRefFor(value);
+
+  Future<Instance?> instanceFor(RemoteObject value) =>
+      _instanceHelper.instanceFor(value);
+
+  Future<Library?> getLibrary(String objectId) async {
+    final libraryRef = await libraryRefFor(objectId);
+    if (libraryRef == null) return null;
+    return libraryHelper.libraryFor(libraryRef);
+  }
+
+  Future<Obj> getObject(String objectId, {int? offset, int? count}) async {
+    try {
+      final library = await getLibrary(objectId);
+      if (library != null) {
+        return library;
+      }
+      final clazz = await _classHelper.forObjectId(objectId);
+      if (clazz != null) {
+        return clazz;
+      }
+      final scriptRef = scriptRefsById[objectId];
+      if (scriptRef != null) {
+        return _getScript(scriptRef);
+      }
+      final instance = await _instanceHelper.instanceFor(
+        remoteObjectFor(objectId),
+        offset: offset,
+        count: count,
+      );
+      if (instance != null) {
+        return instance;
+      }
+    } catch (e, s) {
+      _logger.fine('getObject $objectId failed', e, s);
+      rethrow;
+    }
+    throw UnsupportedError(
+      'Only libraries, instances, classes, and scripts '
+      'are supported for getObject',
+    );
+  }
+
+  Future<Script> _getScript(ScriptRef scriptRef) async {
+    final scriptId = scriptRef.id;
+    final scriptUri = scriptRef.uri;
+    if (scriptId == null || scriptUri == null) {
+      throwInvalidParam('getObject', 'No script info for script $scriptRef');
+    }
+    final serverPath = DartUri(scriptUri, root).serverPath;
+    final source = await _assetReader.dartSourceContents(serverPath);
+    if (source == null) {
+      throwInvalidParam(
+        'getObject',
+        'No source for $scriptRef  with serverPath: $serverPath',
+      );
+    }
+    final libraryId = scriptIdToLibraryId[scriptId];
+    if (libraryId == null) {
+      throwInvalidParam('getObject', 'No library for script $scriptRef');
+    }
+    return Script(
+        uri: scriptRef.uri,
+        library: await libraryRefFor(libraryId),
+        id: scriptId,
+      )
+      ..tokenPosTable = await _locations.tokenPosTableFor(serverPath)
+      ..source = source;
+  }
+
+  Future<MemoryUsage> getMemoryUsage() async {
+    final response = await remoteDebugger.sendCommand('Runtime.getHeapUsage');
+    final result = response.result;
+    if (result == null) {
+      throw RPCError(
+        'getMemoryUsage',
+        RPCErrorKind.kInternalError.code,
+        'Null result from chrome Devtools.',
+      );
+    }
+    final jsUsage = HeapUsage(result);
+    final usage = MemoryUsage.parse({
+      'heapUsage': jsUsage.usedSize,
+      'heapCapacity': jsUsage.totalSize,
+      'externalUsage': 0,
+    });
+    if (usage == null) {
+      throw RPCError(
+        'getMemoryUsage',
+        RPCErrorKind.kInternalError.code,
+        'Failed to parse memory usage result.',
+      );
+    }
+    return usage;
+  }
+
+  /// Return the VM SourceReport for the given parameters.
+  ///
+  /// Currently this implements the 'PossibleBreakpoints' report kind.
+  Future<SourceReport> getSourceReport(
+    List<String> reports, {
+    String? scriptId,
+  }) {
+    if (reports.contains(SourceReportKind.kCoverage)) {
+      throwInvalidParam(
+        'getSourceReport',
+        'Source report kind ${SourceReportKind.kCoverage} not supported',
+      );
+    }
+
+    if (reports.isEmpty) {
+      throwInvalidParam(
+        'getSourceReport',
+        'Invalid parameter: no value for source report kind provided.',
+      );
+    }
+
+    if (reports.length > 1 ||
+        reports.first != SourceReportKind.kPossibleBreakpoints) {
+      throwInvalidParam('getSourceReport', 'Unsupported source report kind.');
+    }
+
+    return _getPossibleBreakpoints(scriptId);
+  }
+
+  Future<SourceReport> _getPossibleBreakpoints(String? scriptId) async {
+    // TODO(devoncarew): Consider adding some caching for this method.
+
+    final scriptRef = scriptWithId(scriptId);
+    if (scriptRef == null) {
+      throwInvalidParam('getSourceReport', 'scriptRef not found for $scriptId');
+    }
+    final scriptUri = scriptRef.uri;
+    if (scriptUri == null) {
+      throwInvalidParam('getSourceReport', 'scriptUri not found for $scriptId');
+    }
+
+    final dartUri = DartUri(scriptUri, root);
+    final mappedLocations = await _locations.locationsForDart(
+      dartUri.serverPath,
+    );
+    // Unlike the Dart VM, the token positions match exactly to the possible
+    // breakpoints. This is because the token positions are derived from the
+    // DDC source maps which Chrome also uses.
+    final tokenPositions = <int>[
+      for (final location in mappedLocations) location.tokenPos,
+    ];
+    tokenPositions.sort();
+
+    final range = SourceReportRange(
+      scriptIndex: 0,
+      startPos: tokenPositions.isEmpty ? -1 : tokenPositions.first,
+      endPos: tokenPositions.isEmpty ? -1 : tokenPositions.last,
+      compiled: true,
+      possibleBreakpoints: tokenPositions,
+    );
+
+    final ranges = [range];
+    return SourceReport(scripts: [scriptRef], ranges: ranges);
+  }
+
+  /// Calls the Chrome Runtime.getProperties API for the object with [objectId].
+  ///
+  /// Note that the property names are JS names, e.g.
+  /// Symbol(DartClass.actualName) and will need to be converted. For a system
+  /// List or Map, [offset] and/or [count] can be provided to indicate a desired
+  /// range of entries. They will be ignored if there is no [length].
+  Future<List<Property>> getProperties(
+    String objectId, {
+    int? offset,
+    int? count,
+    int? length,
+  }) async {
+    var rangeId = objectId;
+    // Ignore offset/count if there is no length:
+    if (length != null) {
+      if (_isEmptyRange(offset: offset, count: count, length: length)) {
+        return [];
+      }
+      if (_isSubRange(offset: offset, count: count)) {
+        final range = await _subRange(
+          objectId,
+          offset: offset ?? 0,
+          count: count,
+          length: length,
+        );
+        rangeId = range.objectId ?? rangeId;
+      }
+    }
+    final jsProperties = await sendCommandAndValidateResult<List>(
+      remoteDebugger,
+      method: 'Runtime.getProperties',
+      resultField: 'result',
+      params: {'objectId': rangeId, 'ownProperties': true},
+    );
+    return jsProperties
+        .map<Property>((each) => Property(each as Map<String, dynamic>))
+        .where(_isVisibleProperty)
+        .toList();
+  }
+
+  bool _isVisibleProperty(Property property) {
+    // Filter out any RTI objects from the new DDC type system. See:
+    // https://github.com/dart-lang/webdev/issues/2316
+    final isRtiObject =
+        property.value?.className?.startsWith('dart_rti.Rti') ?? false;
+    return !isRtiObject;
+  }
+
+  /// Calculate the number of available elements in the range.
+  static int _calculateRangeCount({
+    int? count,
+    required int offset,
+    required int length,
+  }) => count == null ? length - offset : math.min(count, length - offset);
+
+  /// Find a sub-range of the entries for a Map/List when offset and/or count
+  /// have been specified on a getObject request.
+  ///
+  /// If the object referenced by [id] is not a system List or Map then this
+  /// will just return a RemoteObject for it and ignore [offset], [count] and
+  /// [length]. If it is, then [length] should be the number of entries in the
+  /// List/Map and [offset] and [count] should indicate the desired range.
+  Future<RemoteObject> _subRange(
+    String id, {
+    required int offset,
+    required int length,
+    int? count,
+  }) async {
+    // TODO(#809): Sometimes we already know the type of the object, and
+    // we could take advantage of that to short-circuit.
+    final receiver = remoteObjectFor(id);
+    final rangeCount = _calculateRangeCount(
+      count: count,
+      offset: offset,
+      length: length,
+    );
+    final args = [
+      offset,
+      rangeCount,
+    ].map(dartIdFor).map(remoteObjectFor).toList();
+    // If this is a List, just call sublist. If it's a Map, get the entries, but
+    // avoid doing a toList on a large map using skip/take to get the section we
+    // want. To make those alternatives easier in JS, pass both count and end.
+    final expression = globalToolConfiguration.loadStrategy.dartRuntimeDebugger
+        .getSubRangeJsExpression();
+
+    return await jsCallFunctionOn(receiver, expression, args);
+  }
+
+  static bool _isEmptyRange({required int length, int? offset, int? count}) {
+    if (count == 0) return true;
+    if (offset == null) return false;
+    return offset >= length;
+  }
+
+  static bool _isSubRange({int? offset, int? count}) {
+    if (offset == 0 && count == null) return false;
+    return offset != null || count != null;
+  }
+
+  /// Returns true for objects we display for the user.
+  bool isDisplayableObject(Object? object) =>
+      object is Sentinel ||
+      object is InstanceRef &&
+          !isNativeJsObject(object) &&
+          !isNativeJsError(object);
+
+  /// Returns true for non-dart JavaScript objects.
+  bool isNativeJsObject(InstanceRef instanceRef) {
+    return _instanceHelper.metadataHelper.isNativeJsObject(
+      instanceRef.classRef,
+    );
+  }
+
+  /// Returns true for JavaScript exceptions.
+  bool isNativeJsError(InstanceRef instanceRef) {
+    return _instanceHelper.metadataHelper.isNativeJsError(instanceRef.classRef);
+  }
+
+  /// Runs an eval on the page to compute all existing registered extensions.
+  ///
+  /// Combines this with the RPCs registered in the [isolate]. Use this over
+  /// [Isolate.extensionRPCs] as this computes a live set.
+  ///
+  /// Updates [Isolate.extensionRPCs] to this set.
+  @override
+  Future<Set<String>> getExtensionRpcs() async {
+    final expression = globalToolConfiguration.loadStrategy.dartRuntimeDebugger
+        .getDartDeveloperExtensionNamesJsExpression();
+    final extensionRpcs = <String>{};
+    final params = {
+      'expression': expression,
+      'returnByValue': true,
+      'contextId': await contextId,
+    };
+    try {
+      final response = await remoteDebugger.sendCommand(
+        'Runtime.evaluate',
+        params: params,
+      );
+      final result = getResultOrHandleError(response, evalContents: expression);
+      extensionRpcs.addAll(List.from(result['value'] as List? ?? []));
+    } catch (e, s) {
+      _logger.severe(
+        'Error calling Runtime.evaluate with params $params',
+        e,
+        s,
+      );
+    }
+    isolate.extensionRPCs = List<String>.of(extensionRpcs);
+    return extensionRpcs;
+  }
+
+  /// Convert a JS exception description into a description containing
+  /// a Dart stack trace.
+  Future<String> mapExceptionStackTrace(String description) async {
+    RemoteObject mapperResult;
+    try {
+      mapperResult = await _jsCallFunction(stackTraceMapperExpression, <Object>[
+        description,
+      ]);
+    } catch (_) {
+      return description;
+    }
+    final mappedStack = mapperResult.value?.toString();
+    if (mappedStack == null || mappedStack.isEmpty) {
+      return description;
+    }
+    final message = _allLinesBeforeStackTrace(description);
+    return '$message$mappedStack';
+  }
+
+  String _allLinesBeforeStackTrace(String description) {
+    var message = '';
+    for (final match in exceptionMessageRegex.allMatches(description)) {
+      final isStackTraceLine = stackTraceLineRegex.hasMatch(match[0] ?? '');
+      if (isStackTraceLine) break;
+      message += '${match[0]}\n';
+    }
+    return message;
+  }
+}
diff --git a/dwds/lib/src/debugging/classes.dart b/dwds/lib/src/debugging/classes.dart
index 72d2f467d..9eaf39de1 100644
--- a/dwds/lib/src/debugging/classes.dart
+++ b/dwds/lib/src/debugging/classes.dart
@@ -3,20 +3,21 @@
 // BSD-style license that can be found in the LICENSE file.
 
 import 'package:dwds/src/config/tool_configuration.dart';
+import 'package:dwds/src/debugging/chrome_inspector.dart';
 import 'package:dwds/src/debugging/metadata/class.dart';
 import 'package:dwds/src/services/chrome_debug_exception.dart';
-import 'package:dwds/src/utilities/domain.dart';
 import 'package:dwds/src/utilities/shared.dart';
 import 'package:vm_service/vm_service.dart';
 import 'package:webkit_inspection_protocol/webkit_inspection_protocol.dart';
 
 /// Keeps track of Dart classes available in the running application.
-class ClassHelper extends Domain {
+class ChromeAppClassHelper {
   /// Map of class ID to [Class].
   final _classes = <String, Class>{};
 
-  ClassHelper(AppInspectorInterface appInspector) {
-    inspector = appInspector;
+  final ChromeAppInspector inspector;
+
+  ChromeAppClassHelper(this.inspector) {
     final staticClasses = [
       classRefForClosure,
       classRefForString,
diff --git a/dwds/lib/src/debugging/dart_scope.dart b/dwds/lib/src/debugging/dart_scope.dart
index 7be5ad229..63c825bce 100644
--- a/dwds/lib/src/debugging/dart_scope.dart
+++ b/dwds/lib/src/debugging/dart_scope.dart
@@ -2,7 +2,7 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-import 'package:dwds/src/utilities/domain.dart';
+import 'package:dwds/src/debugging/chrome_inspector.dart';
 import 'package:dwds/src/utilities/objects.dart';
 import 'package:webkit_inspection_protocol/webkit_inspection_protocol.dart';
 
@@ -38,7 +38,7 @@ const ddcCapturedAsyncScope = 'capturedAsyncScope';
 ///
 /// See chromedevtools.github.io/devtools-protocol/tot/Debugger#type-CallFrame.
 Future<List<Property>> visibleVariables({
-  required AppInspectorInterface inspector,
+  required ChromeAppInspector inspector,
   required WipCallFrame frame,
 }) async {
   final allProperties = <Property>[];
diff --git a/dwds/lib/src/debugging/debugger.dart b/dwds/lib/src/debugging/debugger.dart
index ca675889e..832727e64 100644
--- a/dwds/lib/src/debugging/debugger.dart
+++ b/dwds/lib/src/debugging/debugger.dart
@@ -5,8 +5,10 @@
 import 'dart:async';
 
 import 'package:dwds/src/config/tool_configuration.dart';
+import 'package:dwds/src/debugging/chrome_inspector.dart';
 import 'package:dwds/src/debugging/dart_scope.dart';
 import 'package:dwds/src/debugging/frame_computer.dart';
+import 'package:dwds/src/debugging/inspector.dart';
 import 'package:dwds/src/debugging/location.dart';
 import 'package:dwds/src/debugging/remote_debugger.dart';
 import 'package:dwds/src/debugging/skip_list.dart';
@@ -45,7 +47,7 @@ const _pauseModePauseStates = {
 /// e.g. 'packages/myapp/main.dart.lib.js' -> '12'
 final chromePathToRuntimeScriptId = <String, String>{};
 
-class Debugger extends Domain {
+class Debugger {
   static final logger = Logger('Debugger');
 
   final RemoteDebugger _remoteDebugger;
@@ -54,6 +56,8 @@ class Debugger extends Domain {
   final Locations _locations;
   final SkipLists _skipLists;
 
+  late ChromeAppInspector inspector;
+
   int _frameErrorCount = 0;
 
   final StreamController<String> parsedScriptsController =
@@ -107,7 +111,7 @@ class Debugger extends Domain {
   // for more details.
   Completer<void>? _internalPauseCompleter;
 
-  void updateInspector(AppInspectorInterface appInspector) {
+  void updateInspector(ChromeAppInspector appInspector) {
     inspector = appInspector;
     _breakpoints.inspector = appInspector;
   }
@@ -762,7 +766,7 @@ String breakpointIdFor(String scriptId, int line, int column) =>
     'bp/$scriptId#$line:$column';
 
 /// Keeps track of the Dart and JS breakpoint Ids that correspond.
-class _Breakpoints extends Domain {
+class _Breakpoints {
   final _logger = Logger('Breakpoints');
   final _dartIdByJsId = <String, String>{};
   final _jsIdByDartId = <String, String>{};
@@ -774,6 +778,8 @@ class _Breakpoints extends Domain {
   final Locations locations;
   final RemoteDebugger remoteDebugger;
 
+  late AppInspector inspector;
+
   /// The root URI from which the application is served.
   final String root;
 
diff --git a/dwds/lib/src/debugging/inspector.dart b/dwds/lib/src/debugging/inspector.dart
index 3b6d6f029..979fe0d3c 100644
--- a/dwds/lib/src/debugging/inspector.dart
+++ b/dwds/lib/src/debugging/inspector.dart
@@ -2,28 +2,16 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-import 'dart:math' as math;
+import 'dart:collection';
 
 import 'package:async/async.dart';
 import 'package:dwds/src/config/tool_configuration.dart';
 import 'package:dwds/src/connections/app_connection.dart';
-import 'package:dwds/src/debugging/classes.dart';
-import 'package:dwds/src/debugging/debugger.dart';
-import 'package:dwds/src/debugging/execution_context.dart';
-import 'package:dwds/src/debugging/instance.dart';
 import 'package:dwds/src/debugging/libraries.dart';
-import 'package:dwds/src/debugging/location.dart';
 import 'package:dwds/src/debugging/metadata/provider.dart';
-import 'package:dwds/src/debugging/remote_debugger.dart';
-import 'package:dwds/src/loaders/ddc_library_bundle.dart';
-import 'package:dwds/src/readers/asset_reader.dart';
-import 'package:dwds/src/utilities/conversions.dart';
 import 'package:dwds/src/utilities/dart_uri.dart';
-import 'package:dwds/src/utilities/domain.dart';
-import 'package:dwds/src/utilities/objects.dart';
-import 'package:dwds/src/utilities/server.dart';
 import 'package:dwds/src/utilities/shared.dart';
-import 'package:logging/logging.dart';
+import 'package:meta/meta.dart';
 import 'package:vm_service/vm_service.dart';
 import 'package:webkit_inspection_protocol/webkit_inspection_protocol.dart';
 
@@ -32,54 +20,40 @@ import 'package:webkit_inspection_protocol/webkit_inspection_protocol.dart';
 ///
 /// Provides information about currently loaded scripts and objects and support
 /// for eval.
-class AppInspector implements AppInspectorInterface {
+abstract class AppInspector {
   var _scriptCacheMemoizer = AsyncMemoizer<List<ScriptRef>>();
 
   Future<List<ScriptRef>> getScriptRefs({
     ModifiedModuleReport? modifiedModuleReport,
   }) => _populateScriptCaches(modifiedModuleReport: modifiedModuleReport);
 
-  final _logger = Logger('AppInspector');
-
   /// Map of scriptRef ID to [ScriptRef].
+  UnmodifiableMapView<String, ScriptRef> get scriptRefsById =>
+      UnmodifiableMapView(_scriptRefsById);
   final _scriptRefsById = <String, ScriptRef>{};
 
   /// Map of Dart server path to [ScriptRef].
   final _serverPathToScriptRef = <String, ScriptRef>{};
 
   /// Map of [ScriptRef] id to containing [LibraryRef] id.
+  UnmodifiableMapView<String, String> get scriptIdToLibraryId =>
+      UnmodifiableMapView(_scriptIdToLibraryId);
   final _scriptIdToLibraryId = <String, String>{};
 
   /// Map of [Library] id to included [ScriptRef]s.
   final _libraryIdToScriptRefs = <String, List<ScriptRef>>{};
 
-  @override
-  RemoteDebugger get remoteDebugger => _remoteDebugger;
-  final RemoteDebugger _remoteDebugger;
-
-  @override
-  Isolate get isolate => _isolate;
-  final Isolate _isolate;
-
-  @override
-  IsolateRef get isolateRef => _isolateRef;
-  final IsolateRef _isolateRef;
-
-  @override
-  AppConnection get appConnection => _appConnection;
-  final AppConnection _appConnection;
+  final Isolate isolate;
 
-  final ExecutionContext _executionContext;
+  final IsolateRef isolateRef;
 
-  late LibraryHelper _libraryHelper;
-  late ClassHelper _classHelper;
-  late InstanceHelper _instanceHelper;
+  final AppConnection appConnection;
 
-  final AssetReader _assetReader;
-  final Locations _locations;
+  @protected
+  LibraryHelper get libraryHelper;
 
   /// The root URI from which the application is served.
-  final String _root;
+  final String root;
 
   /// JavaScript expression that evaluates to the Dart stack trace mapper.
   static const stackTraceMapperExpression = '\$dartStackTraceUtility.mapper';
@@ -88,47 +62,34 @@ class AppInspector implements AppInspectorInterface {
   static final exceptionMessageRegex = RegExp(r'^.*$', multiLine: true);
 
   /// Flutter widget inspector library.
-  Future<LibraryRef?> get flutterWidgetInspectorLibrary => _libraryHelper
+  Future<LibraryRef?> get flutterWidgetInspectorLibrary => libraryHelper
       .libraryRefFor('package:flutter/src/widgets/widget_inspector.dart');
 
   /// Regex used to extract a stack trace line from the exception description.
   static final stackTraceLineRegex = RegExp(r'^\s*at\s.*$', multiLine: true);
 
-  AppInspector._(
-    this._appConnection,
-    this._isolate,
-    this._remoteDebugger,
-    this._assetReader,
-    this._locations,
-    this._root,
-    this._executionContext,
-  ) : _isolateRef = _toIsolateRef(_isolate);
+  AppInspector(this.appConnection, this.isolate, this.root)
+    : isolateRef = _toIsolateRef(isolate);
 
   /// Reset all caches and recompute any mappings.
   ///
   /// Should be called across hot reloads with a valid [ModifiedModuleReport].
+  @protected
+  @mustCallSuper
   Future<void> initialize({ModifiedModuleReport? modifiedModuleReport}) async {
     _scriptCacheMemoizer = AsyncMemoizer<List<ScriptRef>>();
 
-    // TODO(srujzs): We can invalidate these in a smarter way instead of
-    // reinitializing when doing a hot reload, but these helpers recompute info
-    // on demand later and therefore are not in the critical path.
-    _classHelper = ClassHelper(this);
-    _instanceHelper = InstanceHelper(this);
-
-    if (modifiedModuleReport != null) {
-      // Invalidate `_libraryHelper` as we use it populate any script caches.
-      _libraryHelper.initialize(modifiedModuleReport: modifiedModuleReport);
-    } else {
-      _libraryHelper = LibraryHelper(this)..initialize();
+    // Invalidate `_libraryHelper` as we use it populate any script caches.
+    libraryHelper.initialize(modifiedModuleReport: modifiedModuleReport);
+    if (modifiedModuleReport == null) {
       _scriptRefsById.clear();
       _serverPathToScriptRef.clear();
       _scriptIdToLibraryId.clear();
       _libraryIdToScriptRefs.clear();
     }
 
-    final libraries = await _libraryHelper.libraryRefs;
-    isolate.rootLib = await _libraryHelper.rootLib;
+    final libraries = await libraryHelper.libraryRefs;
+    isolate.rootLib = await libraryHelper.rootLib;
     isolate.libraries?.clear();
     isolate.libraries?.addAll(libraries);
 
@@ -149,581 +110,26 @@ class AppInspector implements AppInspectorInterface {
     isSystemIsolate: isolate.isSystemIsolate,
   );
 
-  static Future<AppInspector> create(
-    AppConnection appConnection,
-    RemoteDebugger remoteDebugger,
-    AssetReader assetReader,
-    Locations locations,
-    String root,
-    Debugger debugger,
-    ExecutionContext executionContext,
-  ) async {
-    final id = createId();
-    final time = DateTime.now().millisecondsSinceEpoch;
-    final name = 'main()';
-    final isolate = Isolate(
-      id: id,
-      number: id,
-      name: name,
-      startTime: time,
-      runnable: true,
-      pauseOnExit: false,
-      pauseEvent: Event(
-        kind: EventKind.kPauseStart,
-        timestamp: time,
-        isolate: IsolateRef(
-          id: id,
-          name: name,
-          number: id,
-          isSystemIsolate: false,
-        ),
-      ),
-      livePorts: 0,
-      libraries: [],
-      breakpoints: [],
-      exceptionPauseMode: debugger.pauseState,
-      isSystemIsolate: false,
-      isolateFlags: [],
-    )..extensionRPCs = [];
-    final inspector = AppInspector._(
-      appConnection,
-      isolate,
-      remoteDebugger,
-      assetReader,
-      locations,
-      root,
-      executionContext,
-    );
-
-    debugger.updateInspector(inspector);
-    await inspector.initialize();
-    return inspector;
-  }
-
-  /// Returns the ID for the execution context or null if not found.
-  @override
-  Future<int?> get contextId async {
-    try {
-      return await _executionContext.id;
-    } catch (e, s) {
-      _logger.severe('Missing execution context ID: ', e, s);
-      return null;
-    }
-  }
-
-  /// Get the value of the field named [fieldName] from [receiver].
-  @override
-  Future<RemoteObject> loadField(RemoteObject receiver, String fieldName) {
-    final load = globalToolConfiguration.loadStrategy.dartRuntimeDebugger
-        .getPropertyJsExpression(fieldName);
-    return jsCallFunctionOn(receiver, load, []);
-  }
-
-  /// Call a method by name on [receiver], with arguments [positionalArgs] and
-  /// [namedArgs].
-  Future<RemoteObject> _invokeMethod(
-    RemoteObject receiver,
-    String methodName, [
-    List<RemoteObject> positionalArgs = const [],
-    Map namedArgs = const {},
-  ]) async {
-    // TODO(alanknight): Support named arguments.
-    if (namedArgs.isNotEmpty) {
-      throw UnsupportedError('Named arguments are not yet supported');
-    }
-    // We use the JS pseudo-variable 'arguments' to get the list of all arguments.
-    final send = globalToolConfiguration.loadStrategy.dartRuntimeDebugger
-        .callInstanceMethodJsExpression(methodName);
-    final remote = await jsCallFunctionOn(receiver, send, positionalArgs);
-    return remote;
-  }
-
-  /// Calls Chrome's Runtime.callFunctionOn method.
-  ///
-  /// [evalExpression] should be a JS function definition that can accept
-  /// [arguments].
-  @override
-  Future<RemoteObject> jsCallFunctionOn(
-    RemoteObject receiver,
-    String evalExpression,
-    List<RemoteObject> arguments, {
-    bool returnByValue = false,
-  }) async {
-    final jsArguments = arguments.map(callArgumentFor).toList();
-    final response = await remoteDebugger.sendCommand(
-      'Runtime.callFunctionOn',
-      params: {
-        'functionDeclaration': evalExpression,
-        'arguments': jsArguments,
-        'objectId': receiver.objectId,
-        'returnByValue': returnByValue,
-      },
-    );
-    final result = getResultOrHandleError(
-      response,
-      evalContents: evalExpression,
-    );
-    return RemoteObject(result);
-  }
-
-  /// Calls Chrome's Runtime.callFunctionOn method with a global function.
-  ///
-  /// [evalExpression] should be a JS function definition that can accept
-  /// [arguments].
-  Future<RemoteObject> _jsCallFunction(
-    String evalExpression,
-    List<Object> arguments, {
-    bool returnByValue = false,
-  }) async {
-    final jsArguments = arguments.map(callArgumentFor).toList();
-    final response = await remoteDebugger.sendCommand(
-      'Runtime.callFunctionOn',
-      params: {
-        'functionDeclaration': evalExpression,
-        'arguments': jsArguments,
-        'executionContextId': await contextId,
-        'returnByValue': returnByValue,
-      },
-    );
-    final result = getResultOrHandleError(
-      response,
-      evalContents: evalExpression,
-    );
-    return RemoteObject(result);
-  }
-
-  /// Invoke the function named [selector] on the object identified by
-  /// [targetId].
-  ///
-  /// The [targetId] can be the URL of a Dart library, in which case this means
-  /// invoking a top-level function. The [arguments] are always strings that are
-  /// Dart object Ids (which can also be Chrome RemoteObject objectIds that are
-  /// for non-Dart JS objects.)
-  @override
-  Future<RemoteObject> invoke(
-    String targetId,
-    String selector, [
-    List<dynamic> arguments = const [],
-  ]) async {
-    final remoteArguments = arguments
-        .cast<String>()
-        .map(remoteObjectFor)
-        .toList();
-    // We special case the Dart library, where invokeMethod won't work because
-    // it's not really a Dart object.
-    if (isLibraryId(targetId)) {
-      final library = await getObject(targetId) as Library;
-      return await _invokeLibraryFunction(library, selector, remoteArguments);
-    } else {
-      return _invokeMethod(
-        remoteObjectFor(targetId),
-        selector,
-        remoteArguments,
-      );
-    }
-  }
-
-  /// Invoke the function named [selector] from [library] with [arguments].
-  Future<RemoteObject> _invokeLibraryFunction(
-    Library library,
-    String selector,
-    List<RemoteObject> arguments,
-  ) {
-    final libraryUri = library.uri;
-    if (libraryUri == null) {
-      throwInvalidParam('invoke', 'library uri is null');
-    }
-    return globalToolConfiguration.loadStrategy is DdcLibraryBundleStrategy
-        ? _evaluateLibraryMethodWithDdcLibraryBundle(
-            libraryUri,
-            selector,
-            arguments,
-          )
-        : _evaluateInLibrary(
-            libraryUri,
-            'function () { return this.$selector.apply(this, arguments); }',
-            arguments,
-          );
-  }
-
-  /// Evaluate [expression] by calling Chrome's Runtime.evaluate.
-  @override
-  Future<RemoteObject> jsEvaluate(
-    String expression, {
-    bool returnByValue = false,
-    bool awaitPromise = false,
-  }) async {
-    // TODO(alanknight): Support a version with arguments if needed.
-    final response = await remoteDebugger.sendCommand(
-      'Runtime.evaluate',
-      params: {
-        'expression': expression,
-        'returnByValue': returnByValue,
-        'awaitPromise': awaitPromise,
-        'contextId': await contextId,
-      },
-    );
-    final result = getResultOrHandleError(response, evalContents: expression);
-    return RemoteObject(result);
-  }
-
-  /// Evaluate the JS function with source [jsFunction] in the context of
-  /// the library identified by [libraryUri] with [arguments].
-  Future<RemoteObject> _evaluateInLibrary(
-    String libraryUri,
-    String jsFunction,
-    List<RemoteObject> arguments,
-  ) async {
-    final findLibraryJsExpression = globalToolConfiguration
-        .loadStrategy
-        .dartRuntimeDebugger
-        .callLibraryMethodJsExpression(libraryUri, jsFunction);
-
-    final remoteLibrary = await jsEvaluate(findLibraryJsExpression);
-    return jsCallFunctionOn(remoteLibrary, jsFunction, arguments);
-  }
-
-  /// Evaluates the specified top-level method [methodName] within the library
-  /// identified by [libraryUri] using the Dart Development Compiler (DDC)
-  /// library bundle strategy with the given optional [arguments].
-  Future<RemoteObject> _evaluateLibraryMethodWithDdcLibraryBundle(
-    String libraryUri,
-    String methodName, [
-    List<RemoteObject> arguments = const [],
-  ]) {
-    final expression = globalToolConfiguration.loadStrategy.dartRuntimeDebugger
-        .callLibraryMethodJsExpression(libraryUri, methodName);
-    return _jsCallFunction(expression, arguments);
-  }
-
-  /// Call [function] with objects referred by [argumentIds] as arguments.
-  @override
-  Future<RemoteObject> callFunction(
-    String function,
-    Iterable<String> argumentIds,
-  ) {
-    final arguments = argumentIds.map(remoteObjectFor).toList();
-    return _jsCallFunction(function, arguments);
-  }
-
-  @override
-  Future<InstanceRef?> instanceRefFor(Object value) =>
-      _instanceHelper.instanceRefFor(value);
-
-  Future<Instance?> instanceFor(RemoteObject value) =>
-      _instanceHelper.instanceFor(value);
-
-  @override
   Future<LibraryRef?> libraryRefFor(String objectId) =>
-      _libraryHelper.libraryRefFor(objectId);
-
-  @override
-  Future<Library?> getLibrary(String objectId) async {
-    final libraryRef = await libraryRefFor(objectId);
-    if (libraryRef == null) return null;
-    return _libraryHelper.libraryFor(libraryRef);
-  }
-
-  @override
-  Future<Obj> getObject(String objectId, {int? offset, int? count}) async {
-    try {
-      final library = await getLibrary(objectId);
-      if (library != null) {
-        return library;
-      }
-      final clazz = await _classHelper.forObjectId(objectId);
-      if (clazz != null) {
-        return clazz;
-      }
-      final scriptRef = _scriptRefsById[objectId];
-      if (scriptRef != null) {
-        return _getScript(scriptRef);
-      }
-      final instance = await _instanceHelper.instanceFor(
-        remoteObjectFor(objectId),
-        offset: offset,
-        count: count,
-      );
-      if (instance != null) {
-        return instance;
-      }
-    } catch (e, s) {
-      _logger.fine('getObject $objectId failed', e, s);
-      rethrow;
-    }
-    throw UnsupportedError(
-      'Only libraries, instances, classes, and scripts '
-      'are supported for getObject',
-    );
-  }
-
-  Future<Script> _getScript(ScriptRef scriptRef) async {
-    final scriptId = scriptRef.id;
-    final scriptUri = scriptRef.uri;
-    if (scriptId == null || scriptUri == null) {
-      throwInvalidParam('getObject', 'No script info for script $scriptRef');
-    }
-    final serverPath = DartUri(scriptUri, _root).serverPath;
-    final source = await _assetReader.dartSourceContents(serverPath);
-    if (source == null) {
-      throwInvalidParam(
-        'getObject',
-        'No source for $scriptRef  with serverPath: $serverPath',
-      );
-    }
-    final libraryId = _scriptIdToLibraryId[scriptId];
-    if (libraryId == null) {
-      throwInvalidParam('getObject', 'No library for script $scriptRef');
-    }
-    return Script(
-        uri: scriptRef.uri,
-        library: await libraryRefFor(libraryId),
-        id: scriptId,
-      )
-      ..tokenPosTable = await _locations.tokenPosTableFor(serverPath)
-      ..source = source;
-  }
-
-  @override
-  Future<MemoryUsage> getMemoryUsage() async {
-    final response = await remoteDebugger.sendCommand('Runtime.getHeapUsage');
-    final result = response.result;
-    if (result == null) {
-      throw RPCError(
-        'getMemoryUsage',
-        RPCErrorKind.kInternalError.code,
-        'Null result from chrome Devtools.',
-      );
-    }
-    final jsUsage = HeapUsage(result);
-    final usage = MemoryUsage.parse({
-      'heapUsage': jsUsage.usedSize,
-      'heapCapacity': jsUsage.totalSize,
-      'externalUsage': 0,
-    });
-    if (usage == null) {
-      throw RPCError(
-        'getMemoryUsage',
-        RPCErrorKind.kInternalError.code,
-        'Failed to parse memory usage result.',
-      );
-    }
-    return usage;
-  }
+      libraryHelper.libraryRefFor(objectId);
 
   /// Returns the [ScriptRef] for the provided Dart server path [uri].
-  @override
   Future<ScriptRef?> scriptRefFor(String uri) async {
     await _populateScriptCaches();
     return _serverPathToScriptRef[uri];
   }
 
   /// Returns the [ScriptRef]s in the library with [libraryId].
-  @override
   Future<List<ScriptRef>> scriptRefsForLibrary(String libraryId) async {
     await _populateScriptCaches();
     return _libraryIdToScriptRefs[libraryId] ?? [];
   }
 
-  /// Return the VM SourceReport for the given parameters.
-  ///
-  /// Currently this implements the 'PossibleBreakpoints' report kind.
-  @override
-  Future<SourceReport> getSourceReport(
-    List<String> reports, {
-    String? scriptId,
-    int? tokenPos,
-    int? endTokenPos,
-    bool? forceCompile,
-    bool? reportLines,
-    List<String>? libraryFilters,
-  }) {
-    if (reports.contains(SourceReportKind.kCoverage)) {
-      throwInvalidParam(
-        'getSourceReport',
-        'Source report kind ${SourceReportKind.kCoverage} not supported',
-      );
-    }
-
-    if (reports.isEmpty) {
-      throwInvalidParam(
-        'getSourceReport',
-        'Invalid parameter: no value for source report kind provided.',
-      );
-    }
-
-    if (reports.length > 1 ||
-        reports.first != SourceReportKind.kPossibleBreakpoints) {
-      throwInvalidParam('getSourceReport', 'Unsupported source report kind.');
-    }
-
-    return _getPossibleBreakpoints(scriptId);
-  }
-
-  Future<SourceReport> _getPossibleBreakpoints(String? scriptId) async {
-    // TODO(devoncarew): Consider adding some caching for this method.
-
-    final scriptRef = scriptWithId(scriptId);
-    if (scriptRef == null) {
-      throwInvalidParam('getSourceReport', 'scriptRef not found for $scriptId');
-    }
-    final scriptUri = scriptRef.uri;
-    if (scriptUri == null) {
-      throwInvalidParam('getSourceReport', 'scriptUri not found for $scriptId');
-    }
-
-    final dartUri = DartUri(scriptUri, _root);
-    final mappedLocations = await _locations.locationsForDart(
-      dartUri.serverPath,
-    );
-    // Unlike the Dart VM, the token positions match exactly to the possible
-    // breakpoints. This is because the token positions are derived from the
-    // DDC source maps which Chrome also uses.
-    final tokenPositions = <int>[
-      for (final location in mappedLocations) location.tokenPos,
-    ];
-    tokenPositions.sort();
-
-    final range = SourceReportRange(
-      scriptIndex: 0,
-      startPos: tokenPositions.isEmpty ? -1 : tokenPositions.first,
-      endPos: tokenPositions.isEmpty ? -1 : tokenPositions.last,
-      compiled: true,
-      possibleBreakpoints: tokenPositions,
-    );
-
-    final ranges = [range];
-    return SourceReport(scripts: [scriptRef], ranges: ranges);
-  }
-
   /// All the scripts in the isolate.
-  @override
   Future<ScriptList> getScripts() async {
     return ScriptList(scripts: await getScriptRefs());
   }
 
-  /// Calls the Chrome Runtime.getProperties API for the object with [objectId].
-  ///
-  /// Note that the property names are JS names, e.g.
-  /// Symbol(DartClass.actualName) and will need to be converted. For a system
-  /// List or Map, [offset] and/or [count] can be provided to indicate a desired
-  /// range of entries. They will be ignored if there is no [length].
-  @override
-  Future<List<Property>> getProperties(
-    String objectId, {
-    int? offset,
-    int? count,
-    int? length,
-  }) async {
-    var rangeId = objectId;
-    // Ignore offset/count if there is no length:
-    if (length != null) {
-      if (_isEmptyRange(offset: offset, count: count, length: length)) {
-        return [];
-      }
-      if (_isSubRange(offset: offset, count: count)) {
-        final range = await _subRange(
-          objectId,
-          offset: offset ?? 0,
-          count: count,
-          length: length,
-        );
-        rangeId = range.objectId ?? rangeId;
-      }
-    }
-    final jsProperties = await sendCommandAndValidateResult<List>(
-      _remoteDebugger,
-      method: 'Runtime.getProperties',
-      resultField: 'result',
-      params: {'objectId': rangeId, 'ownProperties': true},
-    );
-    return jsProperties
-        .map<Property>((each) => Property(each as Map<String, dynamic>))
-        .where(_isVisibleProperty)
-        .toList();
-  }
-
-  bool _isVisibleProperty(Property property) {
-    // Filter out any RTI objects from the new DDC type system. See:
-    // https://github.com/dart-lang/webdev/issues/2316
-    final isRtiObject =
-        property.value?.className?.startsWith('dart_rti.Rti') ?? false;
-    return !isRtiObject;
-  }
-
-  /// Calculate the number of available elements in the range.
-  static int _calculateRangeCount({
-    int? count,
-    required int offset,
-    required int length,
-  }) => count == null ? length - offset : math.min(count, length - offset);
-
-  /// Find a sub-range of the entries for a Map/List when offset and/or count
-  /// have been specified on a getObject request.
-  ///
-  /// If the object referenced by [id] is not a system List or Map then this
-  /// will just return a RemoteObject for it and ignore [offset], [count] and
-  /// [length]. If it is, then [length] should be the number of entries in the
-  /// List/Map and [offset] and [count] should indicate the desired range.
-  Future<RemoteObject> _subRange(
-    String id, {
-    required int offset,
-    required int length,
-    int? count,
-  }) async {
-    // TODO(#809): Sometimes we already know the type of the object, and
-    // we could take advantage of that to short-circuit.
-    final receiver = remoteObjectFor(id);
-    final rangeCount = _calculateRangeCount(
-      count: count,
-      offset: offset,
-      length: length,
-    );
-    final args = [
-      offset,
-      rangeCount,
-    ].map(dartIdFor).map(remoteObjectFor).toList();
-    // If this is a List, just call sublist. If it's a Map, get the entries, but
-    // avoid doing a toList on a large map using skip/take to get the section we
-    // want. To make those alternatives easier in JS, pass both count and end.
-    final expression = globalToolConfiguration.loadStrategy.dartRuntimeDebugger
-        .getSubRangeJsExpression();
-
-    return await jsCallFunctionOn(receiver, expression, args);
-  }
-
-  static bool _isEmptyRange({required int length, int? offset, int? count}) {
-    if (count == 0) return true;
-    if (offset == null) return false;
-    return offset >= length;
-  }
-
-  static bool _isSubRange({int? offset, int? count}) {
-    if (offset == 0 && count == null) return false;
-    return offset != null || count != null;
-  }
-
-  /// Returns true for objects we display for the user.
-  @override
-  bool isDisplayableObject(Object? object) =>
-      object is Sentinel ||
-      object is InstanceRef &&
-          !isNativeJsObject(object) &&
-          !isNativeJsError(object);
-
-  /// Returns true for non-dart JavaScript objects.
-  bool isNativeJsObject(InstanceRef instanceRef) {
-    return _instanceHelper.metadataHelper.isNativeJsObject(
-      instanceRef.classRef,
-    );
-  }
-
-  /// Returns true for JavaScript exceptions.
-  @override
-  bool isNativeJsError(InstanceRef instanceRef) {
-    return _instanceHelper.metadataHelper.isNativeJsError(instanceRef.classRef);
-  }
-
   /// Request and cache `<ScriptRef>`s for all the scripts in the application.
   ///
   /// This populates [_scriptRefsById], [_scriptIdToLibraryId],
@@ -746,7 +152,7 @@ class AppInspector implements AppInspectorInterface {
         // Invalidate any script caches that were computed for the now invalid
         // libraries. They will get repopulated below.
         for (final libraryUri in modifiedModuleReport.modifiedLibraries) {
-          final libraryRef = await _libraryHelper.libraryRefFor(libraryUri);
+          final libraryRef = await libraryHelper.libraryRefFor(libraryUri);
           final libraryId = libraryRef?.id;
           // If this was not a pre-existing library, nothing to invalidate.
           if (libraryId == null) continue;
@@ -759,7 +165,7 @@ class AppInspector implements AppInspectorInterface {
               _scriptRefsById.remove(scriptId);
               _scriptIdToLibraryId.remove(scriptId);
               _serverPathToScriptRef.remove(
-                DartUri(scriptUri, _root).serverPath,
+                DartUri(scriptUri, root).serverPath,
               );
             }
           }
@@ -779,7 +185,7 @@ class AppInspector implements AppInspectorInterface {
           ScriptRef(uri: uri, id: createId()),
           for (final part in parts ?? []) ScriptRef(uri: part, id: createId()),
         ];
-        final libraryRef = await _libraryHelper.libraryRefFor(uri);
+        final libraryRef = await libraryHelper.libraryRefFor(uri);
         final libraryId = libraryRef?.id;
         if (libraryId != null) {
           final libraryIdToScriptRefs = _libraryIdToScriptRefs.putIfAbsent(
@@ -792,7 +198,7 @@ class AppInspector implements AppInspectorInterface {
             if (scriptId != null && scriptUri != null) {
               _scriptRefsById[scriptId] = scriptRef;
               _scriptIdToLibraryId[scriptId] = libraryId;
-              _serverPathToScriptRef[DartUri(scriptUri, _root).serverPath] =
+              _serverPathToScriptRef[DartUri(scriptUri, root).serverPath] =
                   scriptRef;
               libraryIdToScriptRefs.add(scriptRef);
             }
@@ -810,7 +216,6 @@ class AppInspector implements AppInspectorInterface {
   }
 
   /// Look up the script by id in an isolate.
-  @override
   ScriptRef? scriptWithId(String? scriptId) =>
       scriptId == null ? null : _scriptRefsById[scriptId];
 
@@ -820,60 +225,5 @@ class AppInspector implements AppInspectorInterface {
   /// [Isolate.extensionRPCs] as this computes a live set.
   ///
   /// Updates [Isolate.extensionRPCs] to this set.
-  Future<Set<String>> getExtensionRpcs() async {
-    final expression = globalToolConfiguration.loadStrategy.dartRuntimeDebugger
-        .getDartDeveloperExtensionNamesJsExpression();
-    final extensionRpcs = <String>{};
-    final params = {
-      'expression': expression,
-      'returnByValue': true,
-      'contextId': await contextId,
-    };
-    try {
-      final response = await remoteDebugger.sendCommand(
-        'Runtime.evaluate',
-        params: params,
-      );
-      final result = getResultOrHandleError(response, evalContents: expression);
-      extensionRpcs.addAll(List.from(result['value'] as List? ?? []));
-    } catch (e, s) {
-      _logger.severe(
-        'Error calling Runtime.evaluate with params $params',
-        e,
-        s,
-      );
-    }
-    isolate.extensionRPCs = List<String>.of(extensionRpcs);
-    return extensionRpcs;
-  }
-
-  /// Convert a JS exception description into a description containing
-  /// a Dart stack trace.
-  @override
-  Future<String> mapExceptionStackTrace(String description) async {
-    RemoteObject mapperResult;
-    try {
-      mapperResult = await _jsCallFunction(stackTraceMapperExpression, <Object>[
-        description,
-      ]);
-    } catch (_) {
-      return description;
-    }
-    final mappedStack = mapperResult.value?.toString();
-    if (mappedStack == null || mappedStack.isEmpty) {
-      return description;
-    }
-    final message = _allLinesBeforeStackTrace(description);
-    return '$message$mappedStack';
-  }
-
-  String _allLinesBeforeStackTrace(String description) {
-    var message = '';
-    for (final match in exceptionMessageRegex.allMatches(description)) {
-      final isStackTraceLine = stackTraceLineRegex.hasMatch(match[0] ?? '');
-      if (isStackTraceLine) break;
-      message += '${match[0]}\n';
-    }
-    return message;
-  }
+  Future<Set<String>> getExtensionRpcs();
 }
diff --git a/dwds/lib/src/debugging/instance.dart b/dwds/lib/src/debugging/instance.dart
index 4c03dcd52..34b5da734 100644
--- a/dwds/lib/src/debugging/instance.dart
+++ b/dwds/lib/src/debugging/instance.dart
@@ -5,11 +5,10 @@
 import 'dart:math';
 
 import 'package:dwds/src/config/tool_configuration.dart';
-import 'package:dwds/src/debugging/inspector.dart';
+import 'package:dwds/src/debugging/chrome_inspector.dart';
 import 'package:dwds/src/debugging/metadata/class.dart';
 import 'package:dwds/src/debugging/metadata/function.dart';
 import 'package:dwds/src/utilities/conversions.dart';
-import 'package:dwds/src/utilities/domain.dart';
 import 'package:dwds/src/utilities/objects.dart';
 import 'package:dwds/src/utilities/shared.dart';
 import 'package:logging/logging.dart';
@@ -17,14 +16,13 @@ import 'package:vm_service/vm_service.dart';
 import 'package:webkit_inspection_protocol/webkit_inspection_protocol.dart';
 
 /// Contains a set of methods for getting [Instance]s and [InstanceRef]s.
-class InstanceHelper extends Domain {
+class ChromeAppInstanceHelper {
   final _logger = Logger('InstanceHelper');
-  final ClassMetaDataHelper metadataHelper;
+  final ChromeClassMetaDataHelper metadataHelper;
+  final ChromeAppInspector inspector;
 
-  InstanceHelper(AppInspector appInspector)
-    : metadataHelper = ClassMetaDataHelper(appInspector) {
-    inspector = appInspector;
-  }
+  ChromeAppInstanceHelper(this.inspector)
+    : metadataHelper = ChromeClassMetaDataHelper(inspector);
 
   static final InstanceRef kNullInstanceRef = _primitiveInstanceRef(
     InstanceKind.kNull,
@@ -480,7 +478,7 @@ class InstanceHelper extends Domain {
       shape,
       'positionalCount',
     );
-    if (positionalCountObject == null || positionalCountObject.value is! int) {
+    if (positionalCountObject.value is! int) {
       _logger.warning(
         'Unexpected positional count from record: $positionalCountObject',
       );
diff --git a/dwds/lib/src/debugging/libraries.dart b/dwds/lib/src/debugging/libraries.dart
index 4bb07623c..a4ce5a080 100644
--- a/dwds/lib/src/debugging/libraries.dart
+++ b/dwds/lib/src/debugging/libraries.dart
@@ -4,16 +4,18 @@
 
 import 'package:collection/collection.dart';
 import 'package:dwds/src/config/tool_configuration.dart';
+import 'package:dwds/src/debugging/chrome_inspector.dart';
+import 'package:dwds/src/debugging/inspector.dart';
 import 'package:dwds/src/debugging/metadata/class.dart';
 import 'package:dwds/src/debugging/metadata/provider.dart';
 import 'package:dwds/src/services/chrome_debug_exception.dart';
-import 'package:dwds/src/utilities/domain.dart';
 import 'package:logging/logging.dart';
+import 'package:meta/meta.dart';
 import 'package:vm_service/vm_service.dart';
 import 'package:webkit_inspection_protocol/webkit_inspection_protocol.dart';
 
 /// Keeps track of Dart libraries available in the running application.
-class LibraryHelper extends Domain {
+class LibraryHelper<T extends AppInspector> {
   final Logger _logger = Logger('LibraryHelper');
 
   /// Map of library ID to [Library].
@@ -24,14 +26,15 @@ class LibraryHelper extends Domain {
 
   LibraryRef? _rootLib;
 
-  LibraryHelper(AppInspectorInterface appInspector) {
-    inspector = appInspector;
-  }
+  final T inspector;
+
+  LibraryHelper(this.inspector);
 
   /// Initialize any caches.
   ///
   /// If [modifiedModuleReport] is not null, invalidates only modified libraries
   /// from the cache and recomputes values for any eager caches.
+  @mustCallSuper
   void initialize({ModifiedModuleReport? modifiedModuleReport}) {
     _rootLib = null;
     if (modifiedModuleReport != null) {
@@ -93,6 +96,15 @@ class LibraryHelper extends Domain {
     return _libraryRefsById.values.toList();
   }
 
+  Future<LibraryRef?> libraryRefFor(String objectId) async {
+    if (_libraryRefsById.isEmpty) await libraryRefs;
+    return _libraryRefsById[objectId];
+  }
+}
+
+class ChromeLibraryHelper extends LibraryHelper<ChromeAppInspector> {
+  ChromeLibraryHelper(super.inspector);
+
   Future<Library?> libraryFor(LibraryRef libraryRef) async {
     final libraryId = libraryRef.id;
     if (libraryId == null) return null;
@@ -102,11 +114,6 @@ class LibraryHelper extends Domain {
     return _librariesById[libraryId] = library;
   }
 
-  Future<LibraryRef?> libraryRefFor(String objectId) async {
-    if (_libraryRefsById.isEmpty) await libraryRefs;
-    return _libraryRefsById[objectId];
-  }
-
   Future<Library?> _constructLibrary(LibraryRef libraryRef) async {
     final libraryId = libraryRef.id;
     final libraryUri = libraryRef.uri;
diff --git a/dwds/lib/src/debugging/metadata/class.dart b/dwds/lib/src/debugging/metadata/class.dart
index d6c0bd15e..2e336271d 100644
--- a/dwds/lib/src/debugging/metadata/class.dart
+++ b/dwds/lib/src/debugging/metadata/class.dart
@@ -3,8 +3,8 @@
 // BSD-style license that can be found in the LICENSE file.
 
 import 'package:dwds/src/config/tool_configuration.dart';
+import 'package:dwds/src/debugging/chrome_inspector.dart';
 import 'package:dwds/src/services/chrome_debug_exception.dart';
-import 'package:dwds/src/utilities/domain.dart';
 import 'package:logging/logging.dart';
 import 'package:vm_service/vm_service.dart';
 import 'package:webkit_inspection_protocol/webkit_inspection_protocol.dart';
@@ -134,15 +134,15 @@ class ClassMetaData {
 /// Allows to get runtime metadata from DDC runtime
 /// and provides functionality to detect some of the
 /// runtime kinds of objects.
-class ClassMetaDataHelper {
+class ChromeClassMetaDataHelper {
   static final _logger = Logger('ClassMetadata');
 
-  final AppInspectorInterface _inspector;
+  final ChromeAppInspector _inspector;
 
   /// Runtime object kinds for class refs.
   final _runtimeObjectKinds = <String, RuntimeObjectKind>{};
 
-  ClassMetaDataHelper(this._inspector);
+  ChromeClassMetaDataHelper(this._inspector);
 
   /// Returns the [ClassMetaData] for the Chrome [remoteObject].
   ///
diff --git a/dwds/lib/src/debugging/web_socket_inspector.dart b/dwds/lib/src/debugging/web_socket_inspector.dart
new file mode 100644
index 000000000..874b439d7
--- /dev/null
+++ b/dwds/lib/src/debugging/web_socket_inspector.dart
@@ -0,0 +1,78 @@
+// Copyright (c) 2025, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:dwds/src/connections/app_connection.dart';
+import 'package:dwds/src/debugging/inspector.dart';
+import 'package:dwds/src/debugging/libraries.dart';
+import 'package:dwds/src/services/web_socket_proxy_service.dart';
+import 'package:meta/meta.dart';
+import 'package:vm_service/vm_service.dart';
+
+/// Provides information about the currently loaded program.
+class WebSocketAppInspector extends AppInspector {
+  /// Counter for generating unique isolate IDs across page refreshes
+  static int _globalIsolateIdCounter = 0;
+
+  WebSocketAppInspector._(
+    super.appConnection,
+    super.isolate,
+    super.root,
+    this._service,
+  );
+
+  static Future<WebSocketAppInspector> create(
+    WebSocketProxyService service,
+    AppConnection appConnection,
+    String root,
+  ) async {
+    final id = (++_globalIsolateIdCounter).toString();
+    final time = DateTime.now().millisecondsSinceEpoch;
+    final name = 'main()';
+    final isolate = Isolate(
+      id: id,
+      number: id,
+      name: name,
+      startTime: time,
+      runnable: true,
+      pauseOnExit: false,
+      livePorts: 0,
+      libraries: [],
+      breakpoints: [],
+      isSystemIsolate: false,
+      isolateFlags: [],
+    );
+    final inspector = WebSocketAppInspector._(
+      appConnection,
+      isolate,
+      root,
+      service,
+    );
+
+    await inspector.initialize();
+    return inspector;
+  }
+
+  @override
+  @protected
+  late final libraryHelper = LibraryHelper(this);
+
+  final WebSocketProxyService _service;
+
+  /// Invokes the `getExtensionRpcs` service extension, which returns the list
+  /// of registered extensions.
+  ///
+  /// Combines this with the RPCs registered in the [isolate]. Use this over
+  /// [Isolate.extensionRPCs] as this computes a live set.
+  ///
+  /// Updates [Isolate.extensionRPCs] to this set.
+  @override
+  Future<Set<String>> getExtensionRpcs() async {
+    final response = await _service.callServiceExtension('getExtensionRpcs');
+    final extensionRpcs = (response.json!['rpcs'] as List)
+        .cast<String>()
+        .toSet();
+    isolate.extensionRPCs = List.of(extensionRpcs);
+    return extensionRpcs;
+  }
+}
diff --git a/dwds/lib/src/handlers/dev_handler.dart b/dwds/lib/src/handlers/dev_handler.dart
index 3a209c978..a5d25e080 100644
--- a/dwds/lib/src/handlers/dev_handler.dart
+++ b/dwds/lib/src/handlers/dev_handler.dart
@@ -287,6 +287,7 @@ class DevHandler {
     final webSocketDebugService = await WebSocketDebugService.start(
       'localhost',
       appConnection,
+      _assetReader,
       sendClientRequest: _sendRequestToClients,
     );
     return _createAppDebugServicesWebSocketMode(
diff --git a/dwds/lib/src/services/batched_expression_evaluator.dart b/dwds/lib/src/services/batched_expression_evaluator.dart
index af0bd31ca..fbdf9ef5f 100644
--- a/dwds/lib/src/services/batched_expression_evaluator.dart
+++ b/dwds/lib/src/services/batched_expression_evaluator.dart
@@ -6,12 +6,12 @@ import 'dart:async';
 
 import 'package:collection/collection.dart';
 import 'package:dwds/shared/batched_stream.dart';
+import 'package:dwds/src/debugging/chrome_inspector.dart';
 import 'package:dwds/src/debugging/debugger.dart';
 import 'package:dwds/src/debugging/location.dart';
 import 'package:dwds/src/debugging/modules.dart';
 import 'package:dwds/src/services/expression_compiler.dart';
 import 'package:dwds/src/services/expression_evaluator.dart';
-import 'package:dwds/src/utilities/domain.dart';
 import 'package:dwds/src/utilities/shared.dart';
 import 'package:logging/logging.dart';
 import 'package:webkit_inspection_protocol/webkit_inspection_protocol.dart';
@@ -28,7 +28,7 @@ class EvaluateRequest {
 
 class BatchedExpressionEvaluator extends ExpressionEvaluator {
   final _logger = Logger('BatchedExpressionEvaluator');
-  final AppInspectorInterface _inspector;
+  final ChromeAppInspector _inspector;
   final _requestController = BatchedStreamController<EvaluateRequest>(
     delay: 200,
   );
diff --git a/dwds/lib/src/services/chrome_proxy_service.dart b/dwds/lib/src/services/chrome_proxy_service.dart
index 58888d409..09dbcdef8 100644
--- a/dwds/lib/src/services/chrome_proxy_service.dart
+++ b/dwds/lib/src/services/chrome_proxy_service.dart
@@ -10,9 +10,9 @@ import 'package:dwds/data/debug_event.dart';
 import 'package:dwds/data/register_event.dart';
 import 'package:dwds/src/config/tool_configuration.dart';
 import 'package:dwds/src/connections/app_connection.dart';
+import 'package:dwds/src/debugging/chrome_inspector.dart';
 import 'package:dwds/src/debugging/debugger.dart';
 import 'package:dwds/src/debugging/execution_context.dart';
-import 'package:dwds/src/debugging/inspector.dart';
 import 'package:dwds/src/debugging/instance.dart';
 import 'package:dwds/src/debugging/location.dart';
 import 'package:dwds/src/debugging/metadata/provider.dart';
@@ -66,7 +66,7 @@ final class DisconnectNonDartDevelopmentServiceClients extends RPCError {
 }
 
 /// A proxy from the chrome debug protocol to the dart vm service protocol.
-class ChromeProxyService extends ProxyService {
+class ChromeProxyService extends ProxyService<ChromeAppInspector> {
   /// Signals when isolate starts.
   Future<void> get isStarted => _startedCompleter.future;
   Completer<void> _startedCompleter = Completer<void>();
@@ -75,9 +75,6 @@ class ChromeProxyService extends ProxyService {
   Future<void> get isCompilerInitialized => _compilerCompleter.future;
   Completer<void> _compilerCompleter = Completer<void>();
 
-  /// The root at which we're serving.
-  final String root;
-
   final RemoteDebugger remoteDebugger;
   final ExecutionContext executionContext;
 
@@ -93,23 +90,6 @@ class ChromeProxyService extends ProxyService {
   Future<Debugger> get debuggerFuture => _debuggerCompleter.future;
   final _debuggerCompleter = Completer<Debugger>();
 
-  /// Provides variable inspection functionality.
-  AppInspector get inspector {
-    if (_inspector == null) {
-      throw StateError('No running isolate (inspector is not set).');
-    }
-    return _inspector!;
-  }
-
-  AppInspector? _inspector;
-
-  /// Determines if there an isolate running currently.
-  ///
-  /// [_inspector] is `null` iff the isolate is not running,
-  /// for example, before the first isolate starts or during
-  /// a hot restart.
-  bool get _isIsolateRunning => _inspector != null;
-
   StreamSubscription<ConsoleAPIEvent>? _consoleSubscription;
 
   /// If non-null, a resume event should await the result of this after resuming
@@ -133,7 +113,7 @@ class ChromeProxyService extends ProxyService {
 
   ChromeProxyService._(
     super.vm,
-    this.root,
+    super.root,
     this._assetReader,
     this.remoteDebugger,
     this._modules,
@@ -306,7 +286,7 @@ class ChromeProxyService extends ProxyService {
     bool newConnection = false,
   }) async {
     // Inspector is null if the previous isolate is destroyed.
-    if (_isIsolateRunning) {
+    if (isIsolateRunning) {
       throw UnsupportedError(
         'Cannot create multiple isolates for the same app',
       );
@@ -335,7 +315,7 @@ class ChromeProxyService extends ProxyService {
     await _initializeEntrypoint(entrypoint);
 
     debugger.notifyPausedAtStart();
-    _inspector = await AppInspector.create(
+    inspector = await ChromeAppInspector.create(
       appConnection,
       remoteDebugger,
       _assetReader,
@@ -431,7 +411,7 @@ class ChromeProxyService extends ProxyService {
   @override
   void destroyIsolate() {
     _logger.fine('Destroying isolate');
-    if (!_isIsolateRunning) return;
+    if (!isIsolateRunning) return;
 
     final isolate = inspector.isolate;
     final isolateRef = inspector.isolateRef;
@@ -448,7 +428,7 @@ class ChromeProxyService extends ProxyService {
       ),
     );
     vm.isolates?.removeWhere((ref) => ref.id == isolate.id);
-    _inspector = null;
+    inspector = null;
     _expressionEvaluator?.close();
     _consoleSubscription?.cancel();
     _consoleSubscription = null;
@@ -456,7 +436,7 @@ class ChromeProxyService extends ProxyService {
 
   /// Removes the breakpoints in the running isolate.
   Future<void> disableBreakpoints() async {
-    if (!_isIsolateRunning) return;
+    if (!isIsolateRunning) return;
     final isolate = inspector.isolate;
 
     final debugger = await debuggerFuture;
@@ -557,7 +537,7 @@ class ChromeProxyService extends ProxyService {
     Map? args,
   }) async {
     await isInitialized;
-    isolateId ??= _inspector?.isolate.id;
+    isolateId ??= inspector.isolate.id;
     _checkIsolate('callServiceExtension', isolateId);
     args ??= <String, String>{};
     final stringArgs = args.map(
@@ -601,7 +581,7 @@ class ChromeProxyService extends ProxyService {
   ) async {
     try {
       final result = await evaluation();
-      if (!_isIsolateRunning || isolateId != inspector.isolate.id) {
+      if (!isIsolateRunning || isolateId != inspector.isolate.id) {
         _logger.fine(
           'Cannot get evaluation result for isolate $isolateId: '
           ' isolate exited.',
@@ -875,50 +855,28 @@ class ChromeProxyService extends ProxyService {
     String isolateId,
     List<String> reports, {
     String? scriptId,
+    // Note: Ignore the following optional parameters. They are here to match
+    // the VM service interface.
     int? tokenPos,
     int? endTokenPos,
     bool? forceCompile,
     bool? reportLines,
     List<String>? libraryFilters,
-    // Note: Ignore the optional librariesAlreadyCompiled parameter. It is here
-    // to match the VM service interface.
     List<String>? librariesAlreadyCompiled,
   }) => wrapInErrorHandlerAsync(
     'getSourceReport',
-    () => _getSourceReport(
-      isolateId,
-      reports,
-      scriptId: scriptId,
-      tokenPos: tokenPos,
-      endTokenPos: endTokenPos,
-      forceCompile: forceCompile,
-      reportLines: reportLines,
-      libraryFilters: libraryFilters,
-    ),
+    () => _getSourceReport(isolateId, reports, scriptId: scriptId),
   );
 
   Future<SourceReport> _getSourceReport(
     String isolateId,
     List<String> reports, {
     String? scriptId,
-    int? tokenPos,
-    int? endTokenPos,
-    bool? forceCompile,
-    bool? reportLines,
-    List<String>? libraryFilters,
   }) {
     return captureElapsedTime(() async {
       await isInitialized;
       _checkIsolate('getSourceReport', isolateId);
-      return await inspector.getSourceReport(
-        reports,
-        scriptId: scriptId,
-        tokenPos: tokenPos,
-        endTokenPos: endTokenPos,
-        forceCompile: forceCompile,
-        reportLines: reportLines,
-        libraryFilters: libraryFilters,
-      );
+      return await inspector.getSourceReport(reports, scriptId: scriptId);
     }, (result) => DwdsEvent.getSourceReport());
   }
 
@@ -1382,7 +1340,7 @@ class ChromeProxyService extends ProxyService {
         chromeConsoleSubscription = remoteDebugger.onConsoleAPICalled.listen((
           e,
         ) {
-          if (!_isIsolateRunning) return;
+          if (!isIsolateRunning) return;
           final isolateRef = inspector.isolateRef;
           if (!filter(e)) return;
           final args = e.params?['args'] as List?;
@@ -1402,7 +1360,7 @@ class ChromeProxyService extends ProxyService {
           exceptionsSubscription = remoteDebugger.onExceptionThrown.listen((
             e,
           ) async {
-            if (!_isIsolateRunning) return;
+            if (!isIsolateRunning) return;
             final isolateRef = inspector.isolateRef;
             var description = e.exceptionDetails.exception?.description;
             if (description != null) {
@@ -1436,7 +1394,7 @@ class ChromeProxyService extends ProxyService {
   @override
   void parseDebugEvent(DebugEvent debugEvent) {
     if (terminatingIsolates) return;
-    if (!_isIsolateRunning) return;
+    if (!isIsolateRunning) return;
     final isolateRef = inspector.isolateRef;
 
     streamNotify(
@@ -1458,7 +1416,7 @@ class ChromeProxyService extends ProxyService {
   @override
   void parseRegisterEvent(RegisterEvent registerEvent) {
     if (terminatingIsolates) return;
-    if (!_isIsolateRunning) return;
+    if (!isIsolateRunning) return;
 
     final isolate = inspector.isolate;
     final isolateRef = inspector.isolateRef;
@@ -1482,7 +1440,7 @@ class ChromeProxyService extends ProxyService {
     ) async {
       if (terminatingIsolates) return;
       if (event.type != 'debug') return;
-      if (!_isIsolateRunning) return;
+      if (!isIsolateRunning) return;
 
       final isolate = inspector.isolate;
       if (isolateRef.id != isolate.id) return;
@@ -1613,7 +1571,7 @@ class ChromeProxyService extends ProxyService {
 
   Future<InstanceRef> _instanceRef(RemoteObject? obj) async {
     final instance = obj == null ? null : await inspector.instanceRefFor(obj);
-    return instance ?? InstanceHelper.kNullInstanceRef;
+    return instance ?? ChromeAppInstanceHelper.kNullInstanceRef;
   }
 
   /// Validate that isolateId matches the current isolate we're connected to and
diff --git a/dwds/lib/src/services/debug_service.dart b/dwds/lib/src/services/debug_service.dart
index f4c9e5576..9a0bf12f6 100644
--- a/dwds/lib/src/services/debug_service.dart
+++ b/dwds/lib/src/services/debug_service.dart
@@ -421,7 +421,8 @@ class WebSocketDebugService implements DebugService {
 
   static Future<WebSocketDebugService> start(
     String hostname,
-    AppConnection appConnection, {
+    AppConnection appConnection,
+    AssetReader assetReader, {
     required SendClientRequest sendClientRequest,
     UrlEncoder? urlEncoder,
   }) async {
@@ -431,6 +432,7 @@ class WebSocketDebugService implements DebugService {
     final webSocketProxyService = await WebSocketProxyService.create(
       sendClientRequest,
       appConnection,
+      assetReader.basePath,
     );
 
     final handler = _createWebSocketHandler(
diff --git a/dwds/lib/src/services/expression_evaluator.dart b/dwds/lib/src/services/expression_evaluator.dart
index cd1607dce..b8cb71c37 100644
--- a/dwds/lib/src/services/expression_evaluator.dart
+++ b/dwds/lib/src/services/expression_evaluator.dart
@@ -3,6 +3,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 import 'package:dwds/src/config/tool_configuration.dart';
+import 'package:dwds/src/debugging/chrome_inspector.dart';
 import 'package:dwds/src/debugging/dart_scope.dart';
 import 'package:dwds/src/debugging/debugger.dart';
 import 'package:dwds/src/debugging/location.dart';
@@ -10,7 +11,6 @@ import 'package:dwds/src/debugging/modules.dart';
 import 'package:dwds/src/services/expression_compiler.dart';
 import 'package:dwds/src/services/javascript_builder.dart';
 import 'package:dwds/src/utilities/conversions.dart';
-import 'package:dwds/src/utilities/domain.dart';
 import 'package:dwds/src/utilities/objects.dart' as chrome;
 import 'package:logging/logging.dart';
 import 'package:webkit_inspection_protocol/webkit_inspection_protocol.dart';
@@ -33,7 +33,7 @@ class EvaluationErrorKind {
 /// ExpressionCompilerInterface to compile dart expressions to JavaScript.
 class ExpressionEvaluator {
   final String _entrypoint;
-  final AppInspectorInterface _inspector;
+  final ChromeAppInspector _inspector;
   final Debugger _debugger;
   final Locations _locations;
   final Modules _modules;
diff --git a/dwds/lib/src/services/proxy_service.dart b/dwds/lib/src/services/proxy_service.dart
index 192e8c8c7..b46dbafa4 100644
--- a/dwds/lib/src/services/proxy_service.dart
+++ b/dwds/lib/src/services/proxy_service.dart
@@ -10,8 +10,10 @@ import 'package:dwds/data/hot_restart_response.dart';
 import 'package:dwds/data/register_event.dart';
 import 'package:dwds/data/service_extension_response.dart';
 import 'package:dwds/src/connections/app_connection.dart';
+import 'package:dwds/src/debugging/inspector.dart';
 import 'package:dwds/src/events.dart';
 import 'package:dwds/src/utilities/shared.dart';
+import 'package:meta/meta.dart';
 import 'package:pub_semver/pub_semver.dart' as semver;
 import 'package:vm_service/vm_service.dart' as vm_service;
 import 'package:vm_service_interface/vm_service_interface.dart';
@@ -19,12 +21,35 @@ import 'package:vm_service_interface/vm_service_interface.dart';
 const pauseIsolatesOnStartFlag = 'pause_isolates_on_start';
 
 /// Abstract base class for VM service proxy implementations.
-abstract class ProxyService implements VmServiceInterface {
+abstract class ProxyService<InspectorT extends AppInspector>
+    implements VmServiceInterface {
   /// Cache of all existing StreamControllers.
   ///
   /// These are all created through [onEvent].
   final Map<String, StreamController<vm_service.Event>> _streamControllers = {};
 
+  /// Provides variable inspection functionality.
+  InspectorT get inspector {
+    if (_inspector == null) {
+      throw StateError('No running isolate (inspector is not set).');
+    }
+    return _inspector!;
+  }
+
+  @protected
+  set inspector(InspectorT? inspector) {
+    _inspector = inspector;
+  }
+
+  InspectorT? _inspector;
+
+  /// Determines if there an isolate running currently.
+  ///
+  /// [_inspector] is `null` iff the isolate is not running,
+  /// for example, before the first isolate starts or during
+  /// a hot restart.
+  bool get isIsolateRunning => _inspector != null;
+
   /// The root `VM` instance.
   final vm_service.VM _vm;
 
@@ -69,7 +94,10 @@ abstract class ProxyService implements VmServiceInterface {
       _resumeAfterRestartEventsController;
   Map<String, bool> get currentVmServiceFlags => _currentVmServiceFlags;
 
-  ProxyService(this._vm);
+  /// The root at which we're serving.
+  final String root;
+
+  ProxyService(this._vm, this.root);
 
   /// Sends events to stream controllers.
   void streamNotify(String streamId, vm_service.Event event) {
diff --git a/dwds/lib/src/services/web_socket_proxy_service.dart b/dwds/lib/src/services/web_socket_proxy_service.dart
index cb97514f3..ceb68b351 100644
--- a/dwds/lib/src/services/web_socket_proxy_service.dart
+++ b/dwds/lib/src/services/web_socket_proxy_service.dart
@@ -14,6 +14,7 @@ import 'package:dwds/data/register_event.dart';
 import 'package:dwds/data/service_extension_request.dart';
 import 'package:dwds/data/service_extension_response.dart';
 import 'package:dwds/src/connections/app_connection.dart';
+import 'package:dwds/src/debugging/web_socket_inspector.dart';
 import 'package:dwds/src/events.dart';
 import 'package:dwds/src/services/proxy_service.dart';
 import 'package:dwds/src/utilities/dart_uri.dart';
@@ -118,7 +119,7 @@ class _ServiceExtensionTracker {
 }
 
 /// WebSocket-based VM service proxy for web debugging.
-class WebSocketProxyService extends ProxyService {
+class WebSocketProxyService extends ProxyService<WebSocketAppInspector> {
   final _logger = Logger('WebSocketProxyService');
 
   /// Active service extension trackers by request ID.
@@ -144,18 +145,14 @@ class WebSocketProxyService extends ProxyService {
   /// Active connection count for this service.
   int _activeConnectionCount = 0;
 
-  /// Counter for generating unique isolate IDs across page refreshes
-  static int _globalIsolateIdCounter = 0;
-
-  bool get _isIsolateRunning => _isolateRunning;
-
   WebSocketProxyService._(
     this.sendClientRequest,
     vm_service.VM vm,
+    String root,
     this.appConnection,
-  ) : super(vm); // Isolate state
-  vm_service.IsolateRef? _isolateRef;
-  bool _isolateRunning = false;
+  ) : super(vm, root);
+
+  // Isolate state
   vm_service.Event? _currentPauseEvent;
   bool _mainHasStarted = false;
 
@@ -197,29 +194,21 @@ class WebSocketProxyService extends ProxyService {
         });
 
     // If we already have a running isolate, just update the connection and return
-    if (_isIsolateRunning && _isolateRef != null) {
+    if (isIsolateRunning) {
       _logger.fine(
-        'Reusing existing isolate ${_isolateRef!.id} for connection: $connectionId',
+        'Reusing existing isolate ${inspector.isolateRef.id} for connection: $connectionId',
       );
       return;
     }
 
-    // Create isolate reference with unique ID
-    final isolateId = '${++_globalIsolateIdCounter}';
-    final isolateRef = vm_service.IsolateRef(
-      id: isolateId,
-      name: 'main()',
-      number: isolateId,
-      isSystemIsolate: false,
-    );
+    inspector = await WebSocketAppInspector.create(this, appConnection, root);
 
-    _isolateRef = isolateRef;
-    _isolateRunning = true;
+    final isolateRef = inspector.isolateRef;
     vm.isolates?.add(isolateRef);
     final timestamp = DateTime.now().millisecondsSinceEpoch;
 
     _logger.fine(
-      'Created new isolate: $isolateId for connection: $connectionId',
+      'Created new isolate: ${isolateRef.id} for connection: $connectionId',
     );
 
     // Send lifecycle events
@@ -327,13 +316,11 @@ class WebSocketProxyService extends ProxyService {
   void destroyIsolate() {
     _logger.fine('Destroying isolate');
 
-    if (!_isIsolateRunning) {
+    if (!isIsolateRunning) {
       _logger.fine('Isolate already destroyed, ignoring');
       return;
     }
 
-    final isolateRef = _isolateRef;
-
     // Cancel all connection subscriptions
     for (final subscription in _appConnectionDoneSubscriptions.values) {
       subscription.cancel();
@@ -341,23 +328,21 @@ class WebSocketProxyService extends ProxyService {
     _appConnectionDoneSubscriptions.clear();
     _activeConnectionCount = 0;
 
+    final isolateRef = inspector.isolateRef;
     // Send exit event
-    if (isolateRef != null) {
-      _streamNotify(
-        vm_service.EventStreams.kIsolate,
-        vm_service.Event(
-          kind: vm_service.EventKind.kIsolateExit,
-          timestamp: DateTime.now().millisecondsSinceEpoch,
-          isolate: isolateRef,
-        ),
-      );
-    }
+    _streamNotify(
+      vm_service.EventStreams.kIsolate,
+      vm_service.Event(
+        kind: vm_service.EventKind.kIsolateExit,
+        timestamp: DateTime.now().millisecondsSinceEpoch,
+        isolate: isolateRef,
+      ),
+    );
 
-    vm.isolates?.removeWhere((ref) => ref.id == isolateRef?.id);
+    vm.isolates?.removeWhere((ref) => ref.id == isolateRef.id);
 
     // Reset state
-    _isolateRef = null;
-    _isolateRunning = false;
+    inspector = null;
     _currentPauseEvent = null;
     _mainHasStarted = false;
 
@@ -397,14 +382,15 @@ class WebSocketProxyService extends ProxyService {
       wrapInErrorHandlerAsync('getIsolate', () => _getIsolate(isolateId));
 
   Future<vm_service.Isolate> _getIsolate(String isolateId) async {
-    if (!_isIsolateRunning || _isolateRef == null) {
+    final isolate = inspector.isolate;
+    if (!isIsolateRunning) {
       throw vm_service.RPCError(
         'getIsolate',
         vm_service.RPCErrorKind.kInvalidParams.code,
         'No running isolate found for id: $isolateId',
       );
     }
-    if (_isolateRef!.id != isolateId) {
+    if (isolate.id != isolateId) {
       throw vm_service.RPCError(
         'getIsolate',
         vm_service.RPCErrorKind.kInvalidParams.code,
@@ -412,15 +398,7 @@ class WebSocketProxyService extends ProxyService {
       );
     }
 
-    return vm_service.Isolate(
-      id: _isolateRef!.id!,
-      name: _isolateRef!.name,
-      number: _isolateRef!.number,
-      startTime: DateTime.now().millisecondsSinceEpoch,
-      isSystemIsolate: _isolateRef!.isSystemIsolate,
-      runnable: true,
-      pauseEvent: _currentPauseEvent,
-    );
+    return isolate;
   }
 
   /// Adds events to stream controllers.
@@ -436,6 +414,7 @@ class WebSocketProxyService extends ProxyService {
   static Future<WebSocketProxyService> create(
     SendClientRequest sendClientRequest,
     AppConnection appConnection,
+    String root,
   ) async {
     final vm = vm_service.VM(
       name: 'WebSocketDebugProxy',
@@ -454,6 +433,7 @@ class WebSocketProxyService extends ProxyService {
     final service = WebSocketProxyService._(
       sendClientRequest,
       vm,
+      root,
       appConnection,
     );
     safeUnawaited(service.createIsolate(appConnection));
@@ -467,12 +447,13 @@ class WebSocketProxyService extends ProxyService {
   Future<vm_service.VM> _getVM() {
     return captureElapsedTime(() async {
       // Ensure the VM's isolate list is synchronized with our actual state
-      if (_isIsolateRunning && _isolateRef != null) {
+      if (isIsolateRunning) {
+        final isolateRef = inspector.isolateRef;
         // Make sure our isolate is in the VM's isolate list
         final isolateExists =
-            vm.isolates?.any((ref) => ref.id == _isolateRef!.id) ?? false;
+            vm.isolates?.any((ref) => ref.id == isolateRef.id) ?? false;
         if (!isolateExists) {
-          vm.isolates?.add(_isolateRef!);
+          vm.isolates?.add(isolateRef);
         }
       } else {
         // If no isolate is running, make sure the list is empty
@@ -835,7 +816,7 @@ class WebSocketProxyService extends ProxyService {
   /// protocol [Event].
   @override
   void parseRegisterEvent(RegisterEvent registerEvent) {
-    if (!_isIsolateRunning || _isolateRef == null) {
+    if (!isIsolateRunning) {
       _logger.warning('Cannot register service extension - no isolate running');
       return;
     }
@@ -846,7 +827,7 @@ class WebSocketProxyService extends ProxyService {
     final event = vm_service.Event(
       kind: vm_service.EventKind.kServiceExtensionAdded,
       timestamp: DateTime.now().millisecondsSinceEpoch,
-      isolate: _isolateRef!,
+      isolate: inspector.isolateRef,
     );
     event.extensionRPC = service;
 
@@ -866,7 +847,7 @@ class WebSocketProxyService extends ProxyService {
   /// protocol [Event].
   @override
   void parseDebugEvent(DebugEvent debugEvent) {
-    if (!_isIsolateRunning || _isolateRef == null) {
+    if (!isIsolateRunning) {
       _logger.warning('Cannot parse debug event - no isolate running');
       return;
     }
@@ -876,7 +857,7 @@ class WebSocketProxyService extends ProxyService {
       vm_service.Event(
           kind: vm_service.EventKind.kExtension,
           timestamp: DateTime.now().millisecondsSinceEpoch,
-          isolate: _isolateRef!,
+          isolate: inspector.isolateRef,
         )
         ..extensionKind = debugEvent.kind
         ..extensionData = vm_service.ExtensionData.parse(
@@ -903,13 +884,11 @@ class WebSocketProxyService extends ProxyService {
         value == 'true' &&
         oldValue == false) {
       // Send pause event for existing isolate if not already paused
-      if (_isIsolateRunning &&
-          _isolateRef != null &&
-          _currentPauseEvent == null) {
+      if (isIsolateRunning && _currentPauseEvent == null) {
         final pauseEvent = vm_service.Event(
           kind: vm_service.EventKind.kPauseStart,
           timestamp: DateTime.now().millisecondsSinceEpoch,
-          isolate: _isolateRef!,
+          isolate: inspector.isolateRef,
         );
         _currentPauseEvent = pauseEvent;
         _streamNotify(vm_service.EventStreams.kDebug, pauseEvent);
@@ -967,12 +946,12 @@ class WebSocketProxyService extends ProxyService {
     }
 
     // Clear pause state and send resume event to notify debugging tools
-    if (_currentPauseEvent != null && _isolateRef != null) {
+    if (_currentPauseEvent != null) {
       _currentPauseEvent = null;
       final resumeEvent = vm_service.Event(
         kind: vm_service.EventKind.kResume,
         timestamp: DateTime.now().millisecondsSinceEpoch,
-        isolate: _isolateRef!,
+        isolate: inspector.isolateRef,
       );
       _streamNotify(vm_service.EventStreams.kDebug, resumeEvent);
     }
@@ -1022,14 +1001,14 @@ class WebSocketProxyService extends ProxyService {
   }) => wrapInErrorHandlerAsync('getStack', () => _getStack(isolateId));
 
   Future<vm_service.Stack> _getStack(String isolateId) async {
-    if (!_isIsolateRunning || _isolateRef == null) {
+    if (!isIsolateRunning) {
       throw vm_service.RPCError(
         'getStack',
         vm_service.RPCErrorKind.kInvalidParams.code,
         'No running isolate found for id: $isolateId',
       );
     }
-    if (_isolateRef!.id != isolateId) {
+    if (inspector.isolateRef.id != isolateId) {
       throw vm_service.RPCError(
         'getStack',
         vm_service.RPCErrorKind.kInvalidParams.code,
diff --git a/dwds/lib/src/utilities/domain.dart b/dwds/lib/src/utilities/domain.dart
index bfb19204e..df8d5281b 100644
--- a/dwds/lib/src/utilities/domain.dart
+++ b/dwds/lib/src/utilities/domain.dart
@@ -2,138 +2,7 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-import 'package:dwds/src/connections/app_connection.dart';
-import 'package:dwds/src/debugging/remote_debugger.dart';
-import 'package:dwds/src/utilities/objects.dart';
 import 'package:vm_service/vm_service.dart';
-import 'package:webkit_inspection_protocol/webkit_inspection_protocol.dart';
-
-abstract class AppInspectorInterface {
-  /// Connection to the app running in the browser.
-  AppConnection get appConnection;
-
-  /// Remove debugger that supports debugging JS app in the browser.
-  RemoteDebugger get remoteDebugger;
-
-  /// Current running isolate.
-  Isolate get isolate;
-  IsolateRef get isolateRef;
-
-  /// Returns the ID for the execution context or null if not found.
-  Future<int?> get contextId;
-
-  /// Calls Chrome's Runtime.callFunctionOn method.
-  ///
-  /// [evalExpression] should be a JS function definition that can accept
-  /// [arguments].
-  Future<RemoteObject> jsCallFunctionOn(
-    RemoteObject receiver,
-    String evalExpression,
-    List<RemoteObject> arguments, {
-    bool returnByValue = false,
-  });
-
-  /// Returns the [ScriptRef] for the provided Dart server path [uri].
-  Future<ScriptRef?> scriptRefFor(String uri);
-
-  /// Look up the script by id in an isolate.
-  ScriptRef? scriptWithId(String? scriptId);
-
-  /// Returns the [LibraryRef] for the provided Dart [objectId].
-  Future<LibraryRef?> libraryRefFor(String objectId);
-
-  /// Returns the [Library] for the provided Dart [objectId].
-  Future<Library?> getLibrary(String objectId);
-
-  /// Returns the [ScriptRef]s in the library with [libraryId].
-  Future<List<ScriptRef>> scriptRefsForLibrary(String libraryId);
-
-  /// Create an InstanceRef for an object, which may be a RemoteObject, or may
-  /// be something returned by value from Chrome, e.g. number, boolean, or
-  /// String.
-  Future<InstanceRef?> instanceRefFor(Object value);
-
-  /// Get the value of the field named [fieldName] from [receiver].
-  Future<RemoteObject?> loadField(RemoteObject receiver, String fieldName);
-
-  /// Convert a JS exception description into a description containing
-  /// a Dart stack trace.
-  Future<String> mapExceptionStackTrace(String description);
-
-  /// Call [function] with objects referred by [argumentIds] as arguments.
-  Future<RemoteObject> callFunction(
-    String function,
-    Iterable<String> argumentIds,
-  );
-
-  /// Invoke the function named [selector] on the object identified by
-  /// [targetId].
-  ///
-  /// The [targetId] can be the URL of a Dart library, in which case this means
-  /// invoking a top-level function. The [arguments] are always strings that are
-  /// Dart object Ids (which can also be Chrome RemoteObject objectIds that are
-  /// for non-Dart JS objects.)
-  Future<RemoteObject> invoke(
-    String targetId,
-    String selector,
-    List<dynamic> arguments,
-  );
-
-  /// Evaluate [expression] by calling Chrome's `Runtime.evaluate`.
-  Future<RemoteObject> jsEvaluate(
-    String expression, {
-    bool returnByValue = false,
-    bool awaitPromise = false,
-  });
-
-  /// Lookup an `object` from some isolate by its [objectId].
-  Future<Obj> getObject(String objectId, {int offset, int count});
-
-  /// All the scripts in the isolate.
-  Future<ScriptList> getScripts();
-
-  /// Calls the Chrome Runtime.getProperties API for the object with [objectId].
-  ///
-  /// Note that the property names are JS names, e.g.
-  /// Symbol(DartClass.actualName) and will need to be converted. For a system
-  /// List or Map, [offset] and/or [count] can be provided to indicate a desired
-  /// range of entries. They will be ignored if there is no [length].
-  Future<List<Property>> getProperties(
-    String objectId, {
-    int? offset,
-    int? count,
-    int? length,
-  });
-
-  bool isDisplayableObject(Object? object);
-  bool isNativeJsError(InstanceRef instanceRef);
-
-  /// Return the VM SourceReport for the given parameters.
-  ///
-  /// Currently this implements the 'PossibleBreakpoints' report kind.
-  Future<SourceReport> getSourceReport(
-    List<String> reports, {
-    String scriptId,
-    int tokenPos,
-    int endTokenPos,
-    bool forceCompile,
-    bool reportLines,
-    List<String> libraryFilters,
-  });
-
-  /// Lookup current isolate's memory usage statistics.
-  Future<MemoryUsage?> getMemoryUsage();
-}
-
-/// A common superclass to allow implementations of different parts of the
-/// protocol to get access to the inspector and utility functions.
-///
-/// Subclasses should call the super constructor with the AppInspectorProvider.
-abstract class Domain {
-  Domain();
-
-  late AppInspectorInterface inspector;
-}
 
 Never throwInvalidParam(String method, String message) {
   throw RPCError(method, RPCErrorKind.kInvalidParams.code, message);
diff --git a/dwds/test/debugger_test.dart b/dwds/test/debugger_test.dart
index 908b513bc..fc78cbf55 100644
--- a/dwds/test/debugger_test.dart
+++ b/dwds/test/debugger_test.dart
@@ -10,7 +10,6 @@ import 'dart:async';
 
 import 'package:dwds/src/debugging/debugger.dart';
 import 'package:dwds/src/debugging/frame_computer.dart';
-import 'package:dwds/src/debugging/inspector.dart';
 import 'package:dwds/src/debugging/location.dart';
 import 'package:dwds/src/debugging/skip_list.dart';
 import 'package:logging/logging.dart';
@@ -23,7 +22,7 @@ import 'fixtures/debugger_data.dart';
 import 'fixtures/fakes.dart';
 import 'fixtures/utilities.dart';
 
-late AppInspector inspector;
+late FakeChromeAppInspector inspector;
 late Debugger debugger;
 late FakeWebkitDebugger webkitDebugger;
 late StreamController<DebuggerPausedEvent> pausedController;
@@ -97,7 +96,10 @@ void main() async {
       skipLists,
       root,
     );
-    inspector = FakeInspector(webkitDebugger, fakeIsolate: simpleIsolate);
+    inspector = FakeChromeAppInspector(
+      webkitDebugger,
+      fakeIsolate: simpleIsolate,
+    );
     debugger.updateInspector(inspector);
   });
 
@@ -165,7 +167,10 @@ void main() async {
   setUp(() {
     // We need to provide an Isolate so that the code doesn't bail out on a null
     // check before it has a chance to throw.
-    inspector = FakeInspector(webkitDebugger, fakeIsolate: simpleIsolate);
+    inspector = FakeChromeAppInspector(
+      webkitDebugger,
+      fakeIsolate: simpleIsolate,
+    );
     debugger.updateInspector(inspector);
   });
 
@@ -173,7 +178,10 @@ void main() async {
     setUp(() {
       // We need to provide an Isolate so that the code doesn't bail out on a null
       // check before it has a chance to throw.
-      inspector = FakeInspector(webkitDebugger, fakeIsolate: simpleIsolate);
+      inspector = FakeChromeAppInspector(
+        webkitDebugger,
+        fakeIsolate: simpleIsolate,
+      );
       debugger.updateInspector(inspector);
     });
 
diff --git a/dwds/test/expression_evaluator_test.dart b/dwds/test/expression_evaluator_test.dart
index 7f32c276c..1ad7d3e34 100644
--- a/dwds/test/expression_evaluator_test.dart
+++ b/dwds/test/expression_evaluator_test.dart
@@ -37,7 +37,7 @@ void main() async {
 
     late StreamController<DebuggerPausedEvent> pausedController;
     late StreamController<Event> debugEventController;
-    late FakeInspector inspector;
+    late FakeChromeAppInspector inspector;
     setUp(() async {
       final assetReader = FakeAssetReader(sourceMap: '');
       final toolConfiguration = TestToolConfiguration.withLoadStrategy(
@@ -64,7 +64,10 @@ void main() async {
         skipLists,
         root,
       );
-      inspector = FakeInspector(webkitDebugger, fakeIsolate: simpleIsolate);
+      inspector = FakeChromeAppInspector(
+        webkitDebugger,
+        fakeIsolate: simpleIsolate,
+      );
       debugger.updateInspector(inspector);
 
       _evaluator = ExpressionEvaluator(
diff --git a/dwds/test/fixtures/fakes.dart b/dwds/test/fixtures/fakes.dart
index e9bc4ef29..2cd6083b2 100644
--- a/dwds/test/fixtures/fakes.dart
+++ b/dwds/test/fixtures/fakes.dart
@@ -5,6 +5,7 @@
 import 'dart:async';
 
 import 'package:dwds/asset_reader.dart';
+import 'package:dwds/src/debugging/chrome_inspector.dart';
 import 'package:dwds/src/debugging/dart_runtime_debugger.dart';
 import 'package:dwds/src/debugging/execution_context.dart';
 import 'package:dwds/src/debugging/inspector.dart';
@@ -46,17 +47,10 @@ Isolate get simpleIsolate => Isolate(
   isolateFlags: [],
 );
 
-class FakeInspector implements AppInspector {
+class FakeChromeAppInspector extends FakeInspector
+    implements ChromeAppInspector {
+  FakeChromeAppInspector(this._remoteDebugger, {required super.fakeIsolate});
   final WebkitDebugger _remoteDebugger;
-  final List<String> functionsCalled = [];
-  FakeInspector(this._remoteDebugger, {required this.fakeIsolate});
-
-  Isolate fakeIsolate;
-
-  @override
-  Object noSuchMethod(Invocation invocation) {
-    throw UnsupportedError('This is a fake');
-  }
 
   @override
   Future<RemoteObject> callFunction(
@@ -67,38 +61,14 @@ class FakeInspector implements AppInspector {
     return RemoteObject({'type': 'string', 'value': 'true'});
   }
 
-  @override
-  Future<void> initialize({ModifiedModuleReport? modifiedModuleReport}) async {}
-
   @override
   Future<InstanceRef?> instanceRefFor(Object value) async =>
-      InstanceHelper.kNullInstanceRef;
+      ChromeAppInstanceHelper.kNullInstanceRef;
 
   @override
   Future<Obj> getObject(String objectId, {int? offset, int? count}) async =>
       Obj.parse({})!;
 
-  @override
-  Future<ScriptList> getScripts() async => ScriptList(scripts: []);
-
-  @override
-  Future<ScriptRef> scriptRefFor(String uri) async =>
-      ScriptRef(id: 'fake', uri: 'fake://uri');
-
-  @override
-  ScriptRef? scriptWithId(String? scriptId) => null;
-
-  @override
-  Isolate get isolate => fakeIsolate;
-
-  @override
-  IsolateRef get isolateRef => IsolateRef(
-    id: fakeIsolate.id,
-    number: fakeIsolate.number,
-    name: fakeIsolate.name,
-    isSystemIsolate: fakeIsolate.isSystemIsolate,
-  );
-
   @override
   Future<List<Property>> getProperties(
     String objectId, {
@@ -123,6 +93,42 @@ class FakeInspector implements AppInspector {
   bool isNativeJsError(InstanceRef instanceRef) => false;
 }
 
+class FakeInspector implements AppInspector {
+  final List<String> functionsCalled = [];
+  FakeInspector({required this.fakeIsolate});
+
+  Isolate fakeIsolate;
+
+  @override
+  Object noSuchMethod(Invocation invocation) {
+    throw UnsupportedError('This is a fake');
+  }
+
+  @override
+  Future<void> initialize({ModifiedModuleReport? modifiedModuleReport}) async {}
+
+  @override
+  Future<ScriptList> getScripts() async => ScriptList(scripts: []);
+
+  @override
+  Future<ScriptRef> scriptRefFor(String uri) async =>
+      ScriptRef(id: 'fake', uri: 'fake://uri');
+
+  @override
+  ScriptRef? scriptWithId(String? scriptId) => null;
+
+  @override
+  Isolate get isolate => fakeIsolate;
+
+  @override
+  IsolateRef get isolateRef => IsolateRef(
+    id: fakeIsolate.id,
+    number: fakeIsolate.number,
+    name: fakeIsolate.name,
+    isSystemIsolate: fakeIsolate.isSystemIsolate,
+  );
+}
+
 class FakeSseConnection implements SseSocketConnection {
   /// A [StreamController] for incoming messages on SSE connection.
   final controllerIncoming = StreamController<String>();
diff --git a/dwds/test/inspector_test.dart b/dwds/test/inspector_test.dart
index cd52557f3..3909cdc54 100644
--- a/dwds/test/inspector_test.dart
+++ b/dwds/test/inspector_test.dart
@@ -8,7 +8,7 @@ library;
 
 import 'package:dwds/dwds.dart';
 import 'package:dwds/src/config/tool_configuration.dart';
-import 'package:dwds/src/debugging/inspector.dart';
+import 'package:dwds/src/debugging/chrome_inspector.dart';
 import 'package:dwds/src/utilities/conversions.dart';
 import 'package:test/test.dart';
 import 'package:test_common/test_sdk_configuration.dart';
@@ -24,7 +24,7 @@ void main() {
 
   final context = TestContext(TestProject.testScopes, provider);
 
-  late AppInspector inspector;
+  late ChromeAppInspector inspector;
 
   setUpAll(() async {
     await context.setUp();
diff --git a/dwds/test/instances/common/instance_common.dart b/dwds/test/instances/common/instance_common.dart
index a5c040e34..377da0a78 100644
--- a/dwds/test/instances/common/instance_common.dart
+++ b/dwds/test/instances/common/instance_common.dart
@@ -4,7 +4,7 @@
 
 import 'package:dwds/expression_compiler.dart';
 import 'package:dwds/src/config/tool_configuration.dart';
-import 'package:dwds/src/debugging/inspector.dart';
+import 'package:dwds/src/debugging/chrome_inspector.dart';
 import 'package:test/test.dart';
 import 'package:test_common/logging.dart';
 import 'package:test_common/test_sdk_configuration.dart';
@@ -26,7 +26,7 @@ void runTypeSystemVerificationTests({
 
   group('$compilationMode |', () {
     final context = TestContext(project, provider);
-    late AppInspector inspector;
+    late ChromeAppInspector inspector;
 
     setUpAll(() async {
       setCurrentLogWriter(debug: debug);
@@ -87,7 +87,7 @@ void runTests({
   final project = TestProject.testScopes;
   final context = TestContext(project, provider);
 
-  late AppInspector inspector;
+  late ChromeAppInspector inspector;
 
   group('$compilationMode |', () {
     setUpAll(() async {