diff --git a/frontend/appflowy_flutter/lib/plugins/document/application/workspace_overview/workspace_overview_bloc.dart b/frontend/appflowy_flutter/lib/plugins/document/application/workspace_overview/workspace_overview_bloc.dart
index 20ba0fa67fc0..644da6045283 100644
--- a/frontend/appflowy_flutter/lib/plugins/document/application/workspace_overview/workspace_overview_bloc.dart
+++ b/frontend/appflowy_flutter/lib/plugins/document/application/workspace_overview/workspace_overview_bloc.dart
@@ -3,7 +3,6 @@ import 'package:appflowy/workspace/application/view/view_service.dart';
 import 'package:appflowy/workspace/application/workspace/overview/overview_listener.dart';
 import 'package:appflowy_backend/log.dart';
 import 'package:appflowy_backend/protobuf/flowy-folder/view.pb.dart';
-import 'package:dartz/dartz.dart';
 import 'package:flutter_bloc/flutter_bloc.dart';
 import 'package:freezed_annotation/freezed_annotation.dart';
 
@@ -69,18 +68,18 @@ class WorkspaceOverviewBloc
 
     if (update.deleteChildViews.isNotEmpty) {
       final res = update.parentViewId == state.view.id
-          ? Tuple2(state.view, 0)
+          ? (state.view, 0)
           : _getView(update.parentViewId, state.view);
 
       if (res != null) {
-        final ViewPB view = res.value1;
-        final int idx = res.value2;
+        final ViewPB view = res.$1;
+        final int idx = res.$2;
 
         ViewPB? parentView;
         if (view.id != state.view.id && view.hasParentViewId()) {
           parentView = view.parentViewId == state.view.id
               ? state.view
-              : _getView(view.parentViewId, state.view)?.value1;
+              : _getView(view.parentViewId, state.view)?.$1;
         }
 
         final childViews = [...view.childViews];
@@ -103,7 +102,7 @@ class WorkspaceOverviewBloc
     // Retrieve the view specified in `update.parentViewId` from the cached views
     // stored in this state to determine if a rebuild is necessary.
     if (update.updateChildViews.isNotEmpty) {
-      final view = _getView(update.parentViewId, state.view)?.value1;
+      final view = _getView(update.parentViewId, state.view)?.$1;
       final childViews = view != null ? view.childViews : <ViewPB>[];
 
       if (_isRebuildRequired(childViews, update.updateChildViews)) {
@@ -142,11 +141,11 @@ class WorkspaceOverviewBloc
     return false;
   }
 
-  Tuple2? _getView(String viewId, ViewPB view) {
+  (ViewPB, int)? _getView(String viewId, ViewPB view) {
     for (int i = 0; i < view.childViews.length; i++) {
       final child = view.childViews[i];
       if (child.id == viewId) {
-        return Tuple2(child, i);
+        return (child, i);
       }
 
       final result = _getView(viewId, child);
diff --git a/frontend/appflowy_flutter/lib/plugins/document/presentation/editor_plugins/overview/workspace_overview_block_component.dart b/frontend/appflowy_flutter/lib/plugins/document/presentation/editor_plugins/overview/workspace_overview_block_component.dart
index 054b7ba014bd..96c3a6413d65 100644
--- a/frontend/appflowy_flutter/lib/plugins/document/presentation/editor_plugins/overview/workspace_overview_block_component.dart
+++ b/frontend/appflowy_flutter/lib/plugins/document/presentation/editor_plugins/overview/workspace_overview_block_component.dart
@@ -15,8 +15,8 @@ import 'package:appflowy_backend/protobuf/flowy-error/errors.pb.dart';
 import 'package:appflowy_backend/protobuf/flowy-folder/icon.pb.dart';
 import 'package:appflowy_backend/protobuf/flowy-folder/view.pb.dart';
 import 'package:appflowy_editor/appflowy_editor.dart' hide Log;
+import 'package:appflowy_result/appflowy_result.dart';
 import 'package:collection/collection.dart';
-import 'package:dartz/dartz.dart' hide State;
 import 'package:easy_localization/easy_localization.dart' hide TextDirection;
 import 'package:flowy_infra_ui/flowy_infra_ui.dart';
 import 'package:flowy_infra_ui/style_widget/hover.dart';
@@ -104,7 +104,7 @@ class _OverviewBlockWidgetState extends State<WorkspaceOverviewBlockWidget>
   late final Animation<double> _curvedAnimationExpansionController;
   static const _expansionAnimationDuration = Duration(milliseconds: 400);
 
-  late Future<Either<ViewPB, FlowyError>>? _future;
+  late Future<FlowyResult<ViewPB, FlowyError>>? _future;
 
   @override
   void initState() {
@@ -129,13 +129,13 @@ class _OverviewBlockWidgetState extends State<WorkspaceOverviewBlockWidget>
 
   @override
   Widget build(BuildContext context) {
-    return FutureBuilder<Either<ViewPB, FlowyError>>(
+    return FutureBuilder<FlowyResult<ViewPB, FlowyError>>(
       future: _future,
       builder: (context, snapshot) {
         if (snapshot.connectionState == ConnectionState.done &&
             snapshot.hasData &&
             snapshot.data != null) {
-          final view = snapshot.data!.getLeftOrNull<ViewPB>();
+          final view = snapshot.data!.toNullable();
           if (view == null) return _buildErrorWidget(viewId);
 
           return BlocProvider<WorkspaceOverviewBloc>(
@@ -397,7 +397,7 @@ class OverviewItemWidget extends StatelessWidget {
 
   Future<ViewPB?> _fetchView(String id) async {
     final view = await ViewBackendService.getView(id).then(
-      (value) => value.swap().toOption().toNullable(),
+      (value) => value.toNullable(),
     );
 
     if (view == null) {
diff --git a/frontend/appflowy_flutter/lib/workspace/application/view/view_service.dart b/frontend/appflowy_flutter/lib/workspace/application/view/view_service.dart
index 3a100de9c2cb..ab5515f0ffe8 100644
--- a/frontend/appflowy_flutter/lib/workspace/application/view/view_service.dart
+++ b/frontend/appflowy_flutter/lib/workspace/application/view/view_service.dart
@@ -250,7 +250,7 @@ class ViewBackendService {
     return result;
   }
 
-  static Future<Either<ViewPB, FlowyError>> getAllLevelOfViews(
+  static Future<FlowyResult<ViewPB, FlowyError>> getAllLevelOfViews(
     String viewID,
   ) async {
     final payload = ViewIdPB.create()..value = viewID;
diff --git a/frontend/appflowy_flutter/lib/workspace/application/workspace/overview/overview_listener.dart b/frontend/appflowy_flutter/lib/workspace/application/workspace/overview/overview_listener.dart
index 1ca0e101a601..cdedbc046aa3 100644
--- a/frontend/appflowy_flutter/lib/workspace/application/workspace/overview/overview_listener.dart
+++ b/frontend/appflowy_flutter/lib/workspace/application/workspace/overview/overview_listener.dart
@@ -9,7 +9,7 @@ import 'package:appflowy_backend/protobuf/flowy-folder/notification.pb.dart';
 import 'package:appflowy_backend/protobuf/flowy-folder/view.pb.dart';
 import 'package:appflowy_backend/protobuf/flowy-notification/subject.pb.dart';
 import 'package:appflowy_backend/rust_stream.dart';
-import 'package:dartz/dartz.dart';
+import 'package:appflowy_result/appflowy_result.dart';
 
 // parent view of overview block updated
 typedef ParentViewUpdateNotifier = void Function(ViewPB);
@@ -55,7 +55,7 @@ class WorkspaceOverviewListener {
 
   void _handleObservableType(
     FolderNotification ty,
-    Either<Uint8List, FlowyError> result,
+    FlowyResult<Uint8List, FlowyError> result,
   ) {
     switch (ty) {
       case FolderNotification.DidUpdateWorkspaceOverviewParentView:
@@ -84,12 +84,12 @@ class WorkspaceOverviewListener {
   /// Registers an overview block listener Id in the backend, allowing us to receive
   /// notifications of [FolderNotification.DidUpdateWorkspaceOverviewChildViews] from
   /// all levels of child views to the specified parent view Id listener.
-  static Future<Either<Unit, FlowyError>> addListenerId(String viewId) {
+  static Future<FlowyResult<void, FlowyError>> addListenerId(String viewId) {
     final payload = ViewIdPB.create()..value = viewId;
     return FolderEventRegisterWorkspaceOverviewListenerId(payload).send();
   }
 
-  static Future<Either<Unit, FlowyError>> removeListener(String viewId) {
+  static Future<FlowyResult<void, FlowyError>> removeListener(String viewId) {
     final payload = ViewIdPB.create()..value = viewId;
     return FolderEventRemoveWorkspaceOverviewListenerId(payload).send();
   }