diff --git a/engine/src/flutter/lib/web_ui/lib/src/engine.dart b/engine/src/flutter/lib/web_ui/lib/src/engine.dart
index ed824416a81..d8405c96571 100644
--- a/engine/src/flutter/lib/web_ui/lib/src/engine.dart
+++ b/engine/src/flutter/lib/web_ui/lib/src/engine.dart
@@ -160,8 +160,6 @@ export 'engine/plugins.dart';
 import 'engine/pointer_binding.dart';
 export 'engine/pointer_binding.dart';
 
-// This import is intentionally commented out because the analyzer says it's unused.
-// import 'engine/pointer_converter.dart';
 export 'engine/pointer_converter.dart';
 
 import 'engine/profiler.dart';
@@ -201,8 +199,6 @@ export 'engine/services/message_codec.dart';
 import 'engine/services/message_codecs.dart';
 export 'engine/services/message_codecs.dart';
 
-// This import is intentionally commented out because the analyzer says it's unused.
-// import 'engine/services/serialization.dart';
 export 'engine/services/serialization.dart';
 
 export 'engine/shadow.dart';
diff --git a/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/color_filter.dart b/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/color_filter.dart
index 63b7ddf4c88..71e5b8dacaf 100644
--- a/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/color_filter.dart
+++ b/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/color_filter.dart
@@ -4,9 +4,10 @@
 
 import 'dart:typed_data';
 
-import 'package:ui/src/engine.dart' show listEquals, EngineColorFilter;
+import 'package:ui/src/engine.dart' show EngineColorFilter;
 import 'package:ui/ui.dart' as ui;
 
+import '../util.dart';
 import 'canvaskit_api.dart';
 import 'image_filter.dart';
 import 'skia_object_cache.dart';
diff --git a/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/fonts.dart b/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/fonts.dart
index eedabac2dc1..acaf37bd93c 100644
--- a/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/fonts.dart
+++ b/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/fonts.dart
@@ -6,8 +6,7 @@ import 'dart:convert';
 import 'dart:html' as html;
 import 'dart:typed_data';
 
-import 'package:ui/src/engine.dart' show AssetManager, AssetManagerException;
-
+import '../assets.dart';
 import '../util.dart';
 import 'canvaskit_api.dart';
 import 'font_fallbacks.dart';
diff --git a/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/image.dart b/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/image.dart
index c2d7bcf8c17..a0effa8e1a7 100644
--- a/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/image.dart
+++ b/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/image.dart
@@ -6,9 +6,9 @@ import 'dart:async';
 import 'dart:html' as html;
 import 'dart:typed_data';
 
-import 'package:ui/src/engine.dart' show WebOnlyImageCodecChunkCallback;
 import 'package:ui/ui.dart' as ui;
 
+import '../html_image_codec.dart';
 import '../util.dart';
 import 'canvaskit_api.dart';
 import 'skia_object_cache.dart';
diff --git a/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/initialization.dart b/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/initialization.dart
index 73ed164428e..11a55a17f24 100644
--- a/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/initialization.dart
+++ b/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/initialization.dart
@@ -9,8 +9,9 @@ import 'dart:html' as html;
 import 'dart:js' as js;
 
 import 'package:js/js.dart';
-import 'package:ui/src/engine.dart' show isDesktop, kProfileMode, domRenderer;
+import 'package:ui/src/engine.dart' show kProfileMode, domRenderer;
 
+import '../browser_detection.dart';
 import 'canvaskit_api.dart';
 import 'fonts.dart';
 
diff --git a/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/layer.dart b/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/layer.dart
index 53b636a63bc..9e714fd7b28 100644
--- a/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/layer.dart
+++ b/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/layer.dart
@@ -2,9 +2,10 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import 'package:ui/src/engine.dart' show transformRect, Matrix4;
 import 'package:ui/ui.dart' as ui;
 
+import '../util.dart';
+import '../vector_math.dart';
 import 'canvas.dart';
 import 'embedded_views.dart';
 import 'n_way_canvas.dart';
diff --git a/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/layer_scene_builder.dart b/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/layer_scene_builder.dart
index c5f4e70ac6e..411c13daa48 100644
--- a/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/layer_scene_builder.dart
+++ b/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/layer_scene_builder.dart
@@ -4,9 +4,10 @@
 
 import 'dart:typed_data';
 
-import 'package:ui/src/engine.dart' show toMatrix32, Matrix4;
+import 'package:ui/src/engine.dart' show toMatrix32;
 import 'package:ui/ui.dart' as ui;
 
+import '../vector_math.dart';
 import 'layer.dart';
 import 'layer_tree.dart';
 import 'picture.dart';
diff --git a/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/layer_tree.dart b/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/layer_tree.dart
index 19d4640bdfd..301dc5ac0bb 100644
--- a/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/layer_tree.dart
+++ b/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/layer_tree.dart
@@ -2,10 +2,10 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import 'package:ui/src/engine.dart' show timeAction;
 import 'package:ui/ui.dart' as ui;
 
 import '../../engine.dart' show kProfilePrerollFrame, kProfileApplyFrame;
+import '../profiler.dart';
 import '../vector_math.dart';
 import 'canvas.dart';
 import 'embedded_views.dart';
diff --git a/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/path.dart b/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/path.dart
index e36c954352b..a9ed3864198 100644
--- a/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/path.dart
+++ b/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/path.dart
@@ -5,9 +5,9 @@
 import 'dart:math' as math;
 import 'dart:typed_data';
 
-import 'package:ui/src/engine.dart' show Matrix4;
 import 'package:ui/ui.dart' as ui;
 
+import '../vector_math.dart';
 import 'canvaskit_api.dart';
 import 'path_metrics.dart';
 import 'skia_object_cache.dart';
diff --git a/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/raster_cache.dart b/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/raster_cache.dart
index 28e4272fd63..bfb96257e8e 100644
--- a/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/raster_cache.dart
+++ b/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/raster_cache.dart
@@ -2,9 +2,9 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import 'package:ui/src/engine.dart' show Matrix4;
 import 'package:ui/ui.dart' as ui;
 
+import '../vector_math.dart';
 import 'canvas.dart';
 
 /// A cache of [Picture]s that have already been rasterized.
diff --git a/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/util.dart b/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/util.dart
index 964775d9640..0c8c9dd4529 100644
--- a/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/util.dart
+++ b/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/util.dart
@@ -5,9 +5,10 @@
 import 'dart:math' as math;
 import 'dart:typed_data';
 
-import 'package:ui/src/engine.dart' show transformRect, Matrix4;
 import 'package:ui/ui.dart' as ui;
 
+import '../util.dart';
+import '../vector_math.dart';
 import 'canvaskit_api.dart';
 import 'path.dart';
 
diff --git a/engine/src/flutter/lib/web_ui/lib/src/engine/text/canvas_paragraph.dart b/engine/src/flutter/lib/web_ui/lib/src/engine/text/canvas_paragraph.dart
index feab7962a03..320837ef279 100644
--- a/engine/src/flutter/lib/web_ui/lib/src/engine/text/canvas_paragraph.dart
+++ b/engine/src/flutter/lib/web_ui/lib/src/engine/text/canvas_paragraph.dart
@@ -6,9 +6,10 @@ import 'dart:html' as html;
 
 import 'package:ui/ui.dart' as ui;
 
-import 'package:ui/src/engine.dart' show BitmapCanvas, canonicalizeFontFamily, domRenderer, DomRenderer;
+import 'package:ui/src/engine.dart' show BitmapCanvas, domRenderer, DomRenderer;
 
 import '../profiler.dart';
+import '../util.dart';
 import 'layout_service.dart';
 import 'paint_service.dart';
 import 'paragraph.dart';
diff --git a/engine/src/flutter/lib/web_ui/lib/src/engine/text/line_breaker.dart b/engine/src/flutter/lib/web_ui/lib/src/engine/text/line_breaker.dart
index 4f8d9589922..11ff7e96310 100644
--- a/engine/src/flutter/lib/web_ui/lib/src/engine/text/line_breaker.dart
+++ b/engine/src/flutter/lib/web_ui/lib/src/engine/text/line_breaker.dart
@@ -3,8 +3,8 @@
 // found in the LICENSE file.
 
 import 'package:ui/ui.dart' as ui;
-import 'package:ui/src/engine.dart' show assertionsEnabled;
 
+import '../util.dart';
 import 'line_break_properties.dart';
 import 'unicode_range.dart';
 
diff --git a/engine/src/flutter/lib/web_ui/lib/src/engine/text/measurement.dart b/engine/src/flutter/lib/web_ui/lib/src/engine/text/measurement.dart
index e65a510904e..e8afb1ec22b 100644
--- a/engine/src/flutter/lib/web_ui/lib/src/engine/text/measurement.dart
+++ b/engine/src/flutter/lib/web_ui/lib/src/engine/text/measurement.dart
@@ -8,8 +8,9 @@ import 'dart:math' as math;
 
 import 'package:meta/meta.dart';
 import 'package:ui/ui.dart' as ui;
-import 'package:ui/src/engine.dart' show assertionsEnabled, domRenderer, registerHotRestartListener, window;
+import 'package:ui/src/engine.dart' show domRenderer, registerHotRestartListener, window;
 
+import '../util.dart';
 import '../web_experiments.dart';
 import 'line_break_properties.dart';
 import 'line_breaker.dart';
diff --git a/engine/src/flutter/lib/web_ui/lib/src/engine/text/paint_service.dart b/engine/src/flutter/lib/web_ui/lib/src/engine/text/paint_service.dart
index f7b2e110258..2c77314d81e 100644
--- a/engine/src/flutter/lib/web_ui/lib/src/engine/text/paint_service.dart
+++ b/engine/src/flutter/lib/web_ui/lib/src/engine/text/paint_service.dart
@@ -3,8 +3,9 @@
 // found in the LICENSE file.
 
 import 'package:ui/ui.dart' as ui;
-import 'package:ui/src/engine.dart' show BitmapCanvas, SurfacePaint;
+import 'package:ui/src/engine.dart' show BitmapCanvas;
 
+import '../html/painting.dart';
 import 'canvas_paragraph.dart';
 import 'layout_service.dart';
 import 'paragraph.dart';
diff --git a/engine/src/flutter/lib/web_ui/lib/src/engine/text/ruler.dart b/engine/src/flutter/lib/web_ui/lib/src/engine/text/ruler.dart
index 819ef198950..efadff8676d 100644
--- a/engine/src/flutter/lib/web_ui/lib/src/engine/text/ruler.dart
+++ b/engine/src/flutter/lib/web_ui/lib/src/engine/text/ruler.dart
@@ -6,9 +6,10 @@ import 'dart:html' as html;
 
 import 'package:meta/meta.dart';
 import 'package:ui/ui.dart' as ui;
-import 'package:ui/src/engine.dart' show assertionsEnabled, canonicalizeFontFamily, domRenderer, DomRenderer;
+import 'package:ui/src/engine.dart' show domRenderer, DomRenderer;
 
 import '../browser_detection.dart';
+import '../util.dart';
 import 'measurement.dart';
 import 'paragraph.dart';
 
diff --git a/engine/src/flutter/lib/web_ui/lib/src/engine/text/word_breaker.dart b/engine/src/flutter/lib/web_ui/lib/src/engine/text/word_breaker.dart
index be1cc7b64b0..34e2356ebc8 100644
--- a/engine/src/flutter/lib/web_ui/lib/src/engine/text/word_breaker.dart
+++ b/engine/src/flutter/lib/web_ui/lib/src/engine/text/word_breaker.dart
@@ -2,9 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-
-import 'package:ui/src/engine.dart' show clampInt;
-
+import '../util.dart';
 import 'word_break_properties.dart';
 
 class _FindBreakDirection {
diff --git a/engine/src/flutter/lib/web_ui/lib/src/engine/vector_math.dart b/engine/src/flutter/lib/web_ui/lib/src/engine/vector_math.dart
index 3040b25abaa..7569da379d3 100644
--- a/engine/src/flutter/lib/web_ui/lib/src/engine/vector_math.dart
+++ b/engine/src/flutter/lib/web_ui/lib/src/engine/vector_math.dart
@@ -5,7 +5,7 @@
 import 'dart:math' as math;
 import 'dart:typed_data';
 
-import 'package:ui/src/engine.dart' show assertionsEnabled;
+import 'util.dart';
 
 class Matrix4 {
   final Float32List _m4storage;
diff --git a/engine/src/flutter/lib/web_ui/test/keyboard_test.dart b/engine/src/flutter/lib/web_ui/test/keyboard_test.dart
index 76b2931afc5..2b6978a1d23 100644
--- a/engine/src/flutter/lib/web_ui/test/keyboard_test.dart
+++ b/engine/src/flutter/lib/web_ui/test/keyboard_test.dart
@@ -12,7 +12,7 @@ import 'package:test/test.dart';
 import 'package:ui/src/engine/browser_detection.dart';
 import 'package:ui/src/engine/keyboard.dart';
 import 'package:ui/src/engine/services.dart';
-import 'package:ui/src/engine.dart' show HybridTextEditing;
+import 'package:ui/src/engine/text_editing/text_editing.dart';
 import 'package:ui/ui.dart' as ui;
 
 void main() {