diff --git a/pkg/dev_compiler/pubspec.yaml b/pkg/dev_compiler/pubspec.yaml
index d08bea697d5..f40fa8e3174 100644
--- a/pkg/dev_compiler/pubspec.yaml
+++ b/pkg/dev_compiler/pubspec.yaml
@@ -30,7 +30,6 @@ dev_dependencies:
   browser_launcher: any
   expect: any
   http_multi_server: any
-  js: any
   lints: any
   modular_test: any
   reload_test: any
diff --git a/pkg/dev_compiler/web/stack_trace_mapper.dart b/pkg/dev_compiler/web/stack_trace_mapper.dart
index 4cc41366404..382b231124a 100644
--- a/pkg/dev_compiler/web/stack_trace_mapper.dart
+++ b/pkg/dev_compiler/web/stack_trace_mapper.dart
@@ -6,23 +6,23 @@
 /// on the page compiled with DDC.
 ///
 /// Example JavaScript usage:
-/// $dartStackTraceUtility.addLoadedListener(function() {
-///   // All Dart source maps are now loaded. It is now safe to start your
-///   // Dart application compiled with DDC.
-///   dart_library.start('your_dart_application');
-/// })
 ///
-/// If $dartStackTraceUtility is set, the dart:core StackTrace class calls
-/// $dartStackTraceUtility.mapper(someJSStackTrace)
+/// ```js
+/// $dartStackTraceUtility.setSourceMapProvider(function(modulePath) {
+///   return dartDevEmbedder.debugger.getSourceMap(modulePath);
+/// });
+/// ```
+///
+/// If `$dartStackTraceUtility` is set, the dart:core StackTrace class calls
+/// `$dartStackTraceUtility.mapper(someJSStackTrace)`
 /// to apply source maps.
 ///
 /// This utility can be compiled to JavaScript using Dart2JS while the rest
 /// of the application is compiled with DDC or could be compiled with DDC.
-@JS()
 library;
 
-// ignore: deprecated_member_use
-import 'package:js/js.dart';
+import 'dart:js_interop';
+
 import 'package:path/path.dart' as p;
 import 'package:source_maps/source_maps.dart';
 import 'package:source_span/source_span.dart';
@@ -30,32 +30,27 @@ import 'package:stack_trace/stack_trace.dart';
 
 import 'source_map_stack_trace.dart';
 
-typedef ReadyCallback = void Function();
-
 /// Global object DDC uses to see if a stack trace utility has been registered.
 @JS(r'$dartStackTraceUtility')
 external set dartStackTraceUtility(DartStackTraceUtility value);
 
 @JS(r'$dartLoader.rootDirectories')
-external List get rootDirectories;
+external JSArray<JSString> get _rootDirectories;
 
-typedef StackTraceMapper = String Function(String stackTrace);
-typedef SourceMapProvider = dynamic Function(String modulePath);
-typedef SetSourceMapProvider = void Function(SourceMapProvider);
+typedef SourceMapProvider = JSAny? Function(String modulePath);
 
-@JS()
-@anonymous
-class DartStackTraceUtility {
+extension type DartStackTraceUtility._(JSObject _) implements JSObject {
   external factory DartStackTraceUtility({
-    StackTraceMapper? mapper,
-    SetSourceMapProvider? setSourceMapProvider,
+    required JSFunction<String Function(String rawStackTrace)> mapper,
+    required JSFunction<void Function(JSFunction<SourceMapProvider>)>
+    setSourceMapProvider,
   });
 }
 
 @JS('JSON.stringify')
-external String _stringify(dynamic json);
+external String _stringify(JSAny? json);
 
-/// Source mapping that is waits to parse source maps until they match the uri
+/// Source mapping that waits to parse source maps until they match the uri
 /// of a requested source map.
 ///
 /// This improves startup performance compared to using MappingBundle directly.
@@ -83,7 +78,9 @@ class LazyMapping extends Mapping {
     if (!_bundle.containsMapping(uri)) {
       var rawMap = _provider(uri);
       if (rawMap != null) {
-        var strMap = rawMap is String ? rawMap : _stringify(rawMap);
+        var strMap = rawMap.isA<JSString>()
+            ? (rawMap as JSString).toDart
+            : _stringify(rawMap);
         var mapping = parse(strMap) as SingleMapping;
         mapping
           ..targetUrl = uri
@@ -103,27 +100,31 @@ class LazyMapping extends Mapping {
 
 LazyMapping? _mapping;
 
-List<String> roots = rootDirectories.map((s) => '$s').toList();
+final List<String> roots = _rootDirectories.toDart
+    .map((s) => s.toDart)
+    .toList();
 
 String mapper(String rawStackTrace) {
   var mapping = _mapping;
   if (mapping == null) {
-    // This should not happen if the user has waited for the ReadyCallback
-    // to start the application.
+    // This shouldn't happen if `setSourceMapProvider` was called
+    // before the application was started.
     throw StateError('Source maps are not done loading.');
   }
   var trace = Trace.parse(rawStackTrace);
   return mapStackTrace(mapping, trace, roots: roots).toString();
 }
 
-void setSourceMapProvider(SourceMapProvider provider) {
-  _mapping = LazyMapping(provider);
+void setSourceMapProvider(JSFunction<SourceMapProvider> provider) {
+  _mapping = LazyMapping(
+    (modulePath) => provider.callAsFunction(null, modulePath.toJS),
+  );
 }
 
 void main() {
   // Register with DDC.
   dartStackTraceUtility = DartStackTraceUtility(
-    mapper: allowInterop(mapper),
-    setSourceMapProvider: allowInterop(setSourceMapProvider),
+    mapper: mapper.toJS,
+    setSourceMapProvider: setSourceMapProvider.toJS,
   );
 }