diff --git a/app/lib/account.dart b/app/lib/account.dart
index 3f22a5be..bbb63c64 100644
--- a/app/lib/account.dart
+++ b/app/lib/account.dart
@@ -5,8 +5,8 @@ import 'package:copy_with/copy_with.dart';
 import 'package:equatable/equatable.dart';
 import 'package:flutter/foundation.dart';
 import 'package:logging/logging.dart';
-import 'package:nc_photos/iterable_extension.dart';
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 import 'package:np_common/type.dart';
 import 'package:np_string/np_string.dart';
 import 'package:to_string/to_string.dart';
diff --git a/app/lib/bloc/home_search_suggestion.dart b/app/lib/bloc/home_search_suggestion.dart
index da9d22de..7af230bc 100644
--- a/app/lib/bloc/home_search_suggestion.dart
+++ b/app/lib/bloc/home_search_suggestion.dart
@@ -11,12 +11,12 @@ import 'package:nc_photos/di_container.dart';
 import 'package:nc_photos/entity/collection.dart';
 import 'package:nc_photos/entity/person.dart';
 import 'package:nc_photos/entity/tag.dart';
-import 'package:nc_photos/iterable_extension.dart';
 import 'package:nc_photos/use_case/collection/list_collection.dart';
 import 'package:nc_photos/use_case/list_location_group.dart';
 import 'package:nc_photos/use_case/list_tag.dart';
 import 'package:nc_photos/use_case/person/list_person.dart';
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 import 'package:np_string/np_string.dart';
 import 'package:to_string/to_string.dart';
 import 'package:tuple/tuple.dart';
diff --git a/app/lib/bloc/list_album_share_outlier.dart b/app/lib/bloc/list_album_share_outlier.dart
index 1452e8b8..efaf26d1 100644
--- a/app/lib/bloc/list_album_share_outlier.dart
+++ b/app/lib/bloc/list_album_share_outlier.dart
@@ -10,11 +10,11 @@ import 'package:nc_photos/entity/album/item.dart';
 import 'package:nc_photos/entity/album/provider.dart';
 import 'package:nc_photos/entity/file.dart';
 import 'package:nc_photos/entity/share.dart';
-import 'package:nc_photos/iterable_extension.dart';
 import 'package:nc_photos/object_extension.dart';
 import 'package:nc_photos/use_case/list_share.dart';
 import 'package:nc_photos/use_case/list_sharee.dart';
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 import 'package:np_string/np_string.dart';
 import 'package:to_string/to_string.dart';
 
diff --git a/app/lib/bloc/list_importable_album.dart b/app/lib/bloc/list_importable_album.dart
index 9a78c0d6..73dc6a76 100644
--- a/app/lib/bloc/list_importable_album.dart
+++ b/app/lib/bloc/list_importable_album.dart
@@ -8,11 +8,11 @@ import 'package:nc_photos/entity/album.dart';
 import 'package:nc_photos/entity/album/provider.dart';
 import 'package:nc_photos/entity/file.dart';
 import 'package:nc_photos/entity/file_util.dart' as file_util;
-import 'package:nc_photos/iterable_extension.dart';
 import 'package:nc_photos/remote_storage_util.dart' as remote_storage_util;
 import 'package:nc_photos/use_case/album/list_album.dart';
 import 'package:nc_photos/use_case/ls.dart';
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 import 'package:to_string/to_string.dart';
 
 part 'list_importable_album.g.dart';
diff --git a/app/lib/bloc/list_sharing.dart b/app/lib/bloc/list_sharing.dart
index 81211592..80a75217 100644
--- a/app/lib/bloc/list_sharing.dart
+++ b/app/lib/bloc/list_sharing.dart
@@ -11,7 +11,6 @@ import 'package:nc_photos/entity/file_descriptor.dart';
 import 'package:nc_photos/entity/file_util.dart' as file_util;
 import 'package:nc_photos/entity/share.dart';
 import 'package:nc_photos/event/event.dart';
-import 'package:nc_photos/iterable_extension.dart';
 import 'package:nc_photos/remote_storage_util.dart' as remote_storage_util;
 import 'package:nc_photos/throttler.dart';
 import 'package:nc_photos/use_case/find_file.dart';
@@ -19,6 +18,7 @@ import 'package:nc_photos/use_case/list_share_with_me.dart';
 import 'package:nc_photos/use_case/ls.dart';
 import 'package:nc_photos/use_case/ls_single_file.dart';
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 import 'package:path/path.dart' as path_lib;
 import 'package:to_string/to_string.dart';
 
diff --git a/app/lib/bloc/scan_local_dir.dart b/app/lib/bloc/scan_local_dir.dart
index 15eb7291..efbab194 100644
--- a/app/lib/bloc/scan_local_dir.dart
+++ b/app/lib/bloc/scan_local_dir.dart
@@ -5,9 +5,9 @@ import 'package:logging/logging.dart';
 import 'package:nc_photos/di_container.dart';
 import 'package:nc_photos/entity/local_file.dart';
 import 'package:nc_photos/event/event.dart';
-import 'package:nc_photos/iterable_extension.dart';
 import 'package:nc_photos/use_case/scan_local_dir.dart';
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 import 'package:to_string/to_string.dart';
 
 part 'scan_local_dir.g.dart';
diff --git a/app/lib/bloc/search_suggestion.dart b/app/lib/bloc/search_suggestion.dart
index 8b94c533..b744d93c 100644
--- a/app/lib/bloc/search_suggestion.dart
+++ b/app/lib/bloc/search_suggestion.dart
@@ -2,8 +2,8 @@ import 'package:collection/collection.dart';
 import 'package:flutter/foundation.dart';
 import 'package:flutter_bloc/flutter_bloc.dart';
 import 'package:logging/logging.dart';
-import 'package:nc_photos/iterable_extension.dart';
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 import 'package:np_string/np_string.dart';
 import 'package:to_string/to_string.dart';
 import 'package:tuple/tuple.dart';
diff --git a/app/lib/controller/collection_items_controller.dart b/app/lib/controller/collection_items_controller.dart
index 08075be5..1c2a869a 100644
--- a/app/lib/controller/collection_items_controller.dart
+++ b/app/lib/controller/collection_items_controller.dart
@@ -15,7 +15,6 @@ import 'package:nc_photos/entity/collection_item/new_item.dart';
 import 'package:nc_photos/entity/file_descriptor.dart';
 import 'package:nc_photos/event/event.dart';
 import 'package:nc_photos/exception_event.dart';
-import 'package:nc_photos/list_extension.dart';
 import 'package:nc_photos/object_extension.dart';
 import 'package:nc_photos/rx_extension.dart';
 import 'package:nc_photos/use_case/collection/add_file_to_collection.dart';
@@ -24,6 +23,7 @@ import 'package:nc_photos/use_case/collection/remove_from_collection.dart';
 import 'package:nc_photos/use_case/collection/update_collection_post_load.dart';
 import 'package:nc_photos/use_case/remove.dart';
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 import 'package:rxdart/rxdart.dart';
 
 part 'collection_items_controller.g.dart';
diff --git a/app/lib/entity/album.dart b/app/lib/entity/album.dart
index 54b6e411..01282a69 100644
--- a/app/lib/entity/album.dart
+++ b/app/lib/entity/album.dart
@@ -7,9 +7,9 @@ import 'package:nc_photos/entity/album/provider.dart';
 import 'package:nc_photos/entity/album/sort_provider.dart';
 import 'package:nc_photos/entity/album/upgrader.dart';
 import 'package:nc_photos/entity/file.dart';
-import 'package:nc_photos/iterable_extension.dart';
 import 'package:nc_photos/object_extension.dart';
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 import 'package:np_common/or_null.dart';
 import 'package:np_common/type.dart';
 import 'package:np_string/np_string.dart';
diff --git a/app/lib/entity/album/data_source.dart b/app/lib/entity/album/data_source.dart
index 94e93f07..9adb19d2 100644
--- a/app/lib/entity/album/data_source.dart
+++ b/app/lib/entity/album/data_source.dart
@@ -9,8 +9,8 @@ import 'package:nc_photos/entity/file_descriptor.dart';
 import 'package:nc_photos/entity/sqlite/database.dart' as sql;
 import 'package:nc_photos/exception.dart';
 import 'package:nc_photos/exception_event.dart';
-import 'package:nc_photos/iterable_extension.dart';
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 
 part 'data_source.g.dart';
 
diff --git a/app/lib/entity/album/provider.dart b/app/lib/entity/album/provider.dart
index 2cdd3e46..07415761 100644
--- a/app/lib/entity/album/provider.dart
+++ b/app/lib/entity/album/provider.dart
@@ -7,8 +7,8 @@ import 'package:nc_photos/entity/album.dart';
 import 'package:nc_photos/entity/album/item.dart';
 import 'package:nc_photos/entity/file.dart';
 import 'package:nc_photos/entity/tag.dart';
-import 'package:nc_photos/iterable_extension.dart';
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 import 'package:np_common/or_null.dart';
 import 'package:np_common/type.dart';
 import 'package:to_string/to_string.dart';
diff --git a/app/lib/entity/collection/adapter/album.dart b/app/lib/entity/collection/adapter/album.dart
index a768d8de..7953bbda 100644
--- a/app/lib/entity/collection/adapter/album.dart
+++ b/app/lib/entity/collection/adapter/album.dart
@@ -19,7 +19,6 @@ import 'package:nc_photos/entity/collection_item/util.dart';
 import 'package:nc_photos/entity/file.dart';
 import 'package:nc_photos/entity/file_descriptor.dart';
 import 'package:nc_photos/entity/sharee.dart';
-import 'package:nc_photos/iterable_extension.dart';
 import 'package:nc_photos/object_extension.dart';
 import 'package:nc_photos/use_case/album/add_file_to_album.dart';
 import 'package:nc_photos/use_case/album/edit_album.dart';
@@ -32,6 +31,7 @@ import 'package:nc_photos/use_case/preprocess_album.dart';
 import 'package:nc_photos/use_case/unimport_shared_album.dart';
 import 'package:nc_photos/use_case/update_album_with_actual_items.dart';
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 import 'package:np_common/or_null.dart';
 import 'package:np_common/type.dart';
 import 'package:np_string/np_string.dart';
diff --git a/app/lib/entity/collection_item/sorter.dart b/app/lib/entity/collection_item/sorter.dart
index 346d517a..56d3bf3a 100644
--- a/app/lib/entity/collection_item/sorter.dart
+++ b/app/lib/entity/collection_item/sorter.dart
@@ -4,8 +4,8 @@ import 'package:nc_photos/entity/album/sort_provider.dart';
 import 'package:nc_photos/entity/collection_item.dart';
 import 'package:nc_photos/entity/collection_item/util.dart';
 import 'package:nc_photos/entity/file_descriptor.dart';
-import 'package:nc_photos/iterable_extension.dart';
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 import 'package:tuple/tuple.dart';
 
 part 'sorter.g.dart';
diff --git a/app/lib/entity/file/data_source.dart b/app/lib/entity/file/data_source.dart
index 88c07a46..18e0f0af 100644
--- a/app/lib/entity/file/data_source.dart
+++ b/app/lib/entity/file/data_source.dart
@@ -14,12 +14,12 @@ import 'package:nc_photos/entity/file_util.dart' as file_util;
 import 'package:nc_photos/entity/sqlite/database.dart' as sql;
 import 'package:nc_photos/entity/sqlite/files_query_builder.dart' as sql;
 import 'package:nc_photos/exception.dart';
-import 'package:nc_photos/iterable_extension.dart';
 import 'package:nc_photos/np_api_util.dart';
 import 'package:nc_photos/object_extension.dart';
 import 'package:nc_photos/use_case/compat/v32.dart';
 import 'package:np_api/np_api.dart' as api;
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 import 'package:np_common/or_null.dart';
 import 'package:path/path.dart' as path_lib;
 
diff --git a/app/lib/entity/file/file_cache_manager.dart b/app/lib/entity/file/file_cache_manager.dart
index a462dc53..fc9ea794 100644
--- a/app/lib/entity/file/file_cache_manager.dart
+++ b/app/lib/entity/file/file_cache_manager.dart
@@ -12,10 +12,9 @@ import 'package:nc_photos/entity/sqlite/database.dart' as sql;
 import 'package:nc_photos/entity/sqlite/files_query_builder.dart' as sql;
 import 'package:nc_photos/entity/sqlite/type_converter.dart';
 import 'package:nc_photos/exception.dart';
-import 'package:nc_photos/iterable_extension.dart';
-import 'package:nc_photos/list_util.dart' as list_util;
 import 'package:nc_photos/object_extension.dart';
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 
 part 'file_cache_manager.g.dart';
 
@@ -136,7 +135,7 @@ class FileSqliteCacheUpdater {
         ..where((t) => t.dir.equals(_dirRowId!))
         ..orderBy([(t) => sql.OrderingTerm.asc(t.rowId)]);
       final dirFiles = await dirFileQuery.get();
-      final diff = list_util.diff(dirFiles.map((e) => e.child),
+      final diff = getDiff(dirFiles.map((e) => e.child),
           _childRowIds.sorted(Comparable.compare));
       if (diff.onlyInB.isNotEmpty) {
         await db.batch((batch) {
diff --git a/app/lib/entity/local_file/data_source.dart b/app/lib/entity/local_file/data_source.dart
index 63dae0aa..ddd46dff 100644
--- a/app/lib/entity/local_file/data_source.dart
+++ b/app/lib/entity/local_file/data_source.dart
@@ -2,7 +2,6 @@ import 'package:collection/collection.dart';
 import 'package:logging/logging.dart';
 import 'package:nc_photos/entity/file_util.dart' as file_util;
 import 'package:nc_photos/entity/local_file.dart';
-import 'package:nc_photos/iterable_extension.dart';
 import 'package:nc_photos/mobile/android/android_info.dart';
 import 'package:nc_photos/mobile/android/k.dart' as android;
 import 'package:nc_photos/mobile/share.dart';
@@ -10,6 +9,7 @@ import 'package:nc_photos/object_extension.dart';
 import 'package:nc_photos/stream_extension.dart';
 import 'package:nc_photos_plugin/nc_photos_plugin.dart';
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 
 part 'data_source.g.dart';
 
diff --git a/app/lib/entity/nc_album/data_source.dart b/app/lib/entity/nc_album/data_source.dart
index 1a1e48a9..337dc7e0 100644
--- a/app/lib/entity/nc_album/data_source.dart
+++ b/app/lib/entity/nc_album/data_source.dart
@@ -9,10 +9,10 @@ import 'package:nc_photos/entity/nc_album_item.dart';
 import 'package:nc_photos/entity/sqlite/database.dart' as sql;
 import 'package:nc_photos/entity/sqlite/type_converter.dart';
 import 'package:nc_photos/exception.dart';
-import 'package:nc_photos/list_util.dart' as list_util;
 import 'package:nc_photos/np_api_util.dart';
 import 'package:np_api/np_api.dart' as api;
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 
 part 'data_source.g.dart';
 
@@ -236,7 +236,7 @@ class NcAlbumSqliteDbDataSource implements NcAlbumCacheDataSource {
       final existingItems = await db.ncAlbumItemsByParent(
         parent: dbAlbum!,
       );
-      final diff = list_util.diffWith<NcAlbumItem>(
+      final diff = getDiffWith<NcAlbumItem>(
         existingItems
             .map((e) => SqliteNcAlbumItemConverter.fromSql(
                 account.userId.raw, album.strippedPath, e))
diff --git a/app/lib/entity/recognize_face/data_source.dart b/app/lib/entity/recognize_face/data_source.dart
index 1960d55e..123c6b4c 100644
--- a/app/lib/entity/recognize_face/data_source.dart
+++ b/app/lib/entity/recognize_face/data_source.dart
@@ -9,11 +9,10 @@ import 'package:nc_photos/entity/sqlite/database.dart' as sql;
 import 'package:nc_photos/entity/sqlite/table.dart';
 import 'package:nc_photos/entity/sqlite/type_converter.dart';
 import 'package:nc_photos/exception.dart';
-import 'package:nc_photos/iterable_extension.dart';
-import 'package:nc_photos/map_extension.dart';
 import 'package:nc_photos/np_api_util.dart';
 import 'package:np_api/np_api.dart' as api;
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 import 'package:np_common/type.dart';
 
 part 'data_source.g.dart';
diff --git a/app/lib/entity/search.dart b/app/lib/entity/search.dart
index 2411c745..9e1b6935 100644
--- a/app/lib/entity/search.dart
+++ b/app/lib/entity/search.dart
@@ -2,7 +2,7 @@ import 'package:nc_photos/account.dart';
 import 'package:nc_photos/entity/file.dart';
 import 'package:nc_photos/entity/file_util.dart' as file_util;
 import 'package:nc_photos/entity/sqlite/files_query_builder.dart' as sql;
-import 'package:nc_photos/iterable_extension.dart';
+import 'package:np_collection/np_collection.dart';
 import 'package:to_string/to_string.dart';
 
 part 'search.g.dart';
diff --git a/app/lib/entity/search/data_source.dart b/app/lib/entity/search/data_source.dart
index 15e660b5..af245b22 100644
--- a/app/lib/entity/search/data_source.dart
+++ b/app/lib/entity/search/data_source.dart
@@ -10,12 +10,12 @@ import 'package:nc_photos/entity/search_util.dart' as search_util;
 import 'package:nc_photos/entity/sqlite/database.dart' as sql;
 import 'package:nc_photos/entity/sqlite/files_query_builder.dart' as sql;
 import 'package:nc_photos/entity/sqlite/type_converter.dart';
-import 'package:nc_photos/iterable_extension.dart';
 import 'package:nc_photos/object_extension.dart';
 import 'package:nc_photos/use_case/inflate_file_descriptor.dart';
 import 'package:nc_photos/use_case/list_tagged_file.dart';
 import 'package:nc_photos/use_case/person/list_person_face.dart';
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 import 'package:np_string/np_string.dart';
 
 part 'data_source.g.dart';
diff --git a/app/lib/entity/sqlite/database.dart b/app/lib/entity/sqlite/database.dart
index 692a3161..06c7e85f 100644
--- a/app/lib/entity/sqlite/database.dart
+++ b/app/lib/entity/sqlite/database.dart
@@ -16,6 +16,7 @@ import 'package:nc_photos/mobile/platform.dart'
 import 'package:nc_photos/object_extension.dart';
 import 'package:nc_photos/platform/k.dart' as platform_k;
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 
 part 'database.g.dart';
 part 'database/nc_album_extension.dart';
diff --git a/app/lib/entity/tagged_file/data_source.dart b/app/lib/entity/tagged_file/data_source.dart
index e016290d..9954a51a 100644
--- a/app/lib/entity/tagged_file/data_source.dart
+++ b/app/lib/entity/tagged_file/data_source.dart
@@ -5,10 +5,10 @@ import 'package:nc_photos/entity/file.dart';
 import 'package:nc_photos/entity/tag.dart';
 import 'package:nc_photos/entity/tagged_file.dart';
 import 'package:nc_photos/exception.dart';
-import 'package:nc_photos/iterable_extension.dart';
 import 'package:nc_photos/np_api_util.dart';
 import 'package:np_api/np_api.dart' as api;
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 
 part 'data_source.g.dart';
 
diff --git a/app/lib/future_util.dart b/app/lib/future_util.dart
index 6f6d6dcb..1f9e9805 100644
--- a/app/lib/future_util.dart
+++ b/app/lib/future_util.dart
@@ -1,6 +1,6 @@
 import 'dart:async';
 
-import 'package:nc_photos/iterable_extension.dart';
+import 'package:np_collection/np_collection.dart';
 
 Future<List<T>> waitOr<T>(
   Iterable<Future<T>> futures,
diff --git a/app/lib/internal_download_handler.dart b/app/lib/internal_download_handler.dart
index 27c0a52a..b5456a18 100644
--- a/app/lib/internal_download_handler.dart
+++ b/app/lib/internal_download_handler.dart
@@ -7,15 +7,14 @@ import 'package:nc_photos/app_localizations.dart';
 import 'package:nc_photos/entity/file.dart';
 import 'package:nc_photos/entity/file_util.dart' as file_util;
 import 'package:nc_photos/exception_util.dart' as exception_util;
-import 'package:nc_photos/iterable_extension.dart';
 import 'package:nc_photos/k.dart' as k;
-import 'package:nc_photos/map_extension.dart';
 import 'package:nc_photos/snack_bar_manager.dart';
 import 'package:nc_photos/use_case/download_file.dart';
 import 'package:nc_photos/use_case/download_preview.dart';
 import 'package:nc_photos/widget/processing_dialog.dart';
 import 'package:nc_photos_plugin/nc_photos_plugin.dart';
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 
 part 'internal_download_handler.g.dart';
 
diff --git a/app/lib/iterable_extension.dart b/app/lib/iterable_extension.dart
index 0b3de2f0..ffbc146f 100644
--- a/app/lib/iterable_extension.dart
+++ b/app/lib/iterable_extension.dart
@@ -1,62 +1,9 @@
 import 'dart:async';
 
-import 'package:collection/collection.dart';
 import 'package:flutter/foundation.dart';
-import 'package:nc_photos/list_extension.dart';
-import 'package:nc_photos/override_comparator.dart';
-import 'package:quiver/iterables.dart';
-import 'package:tuple/tuple.dart';
+import 'package:np_collection/np_collection.dart';
 
 extension IterableExtension<T> on Iterable<T> {
-  /// Return a new stable sorted list
-  List<T> stableSorted([int Function(T a, T b)? compare]) =>
-      toList()..stableSort(compare);
-
-  /// Return a string representation of this iterable by joining the result of
-  /// toString for each items
-  String toReadableString() => "[${join(', ')}]";
-
-  Iterable<Tuple2<int, T>> withIndex() => mapIndexed((i, e) => Tuple2(i, e));
-
-  /// Whether the collection contains an element equal to [element] using the
-  /// equality function [equalFn]
-  bool containsIf(T element, bool Function(T a, T b) equalFn) =>
-      any((e) => equalFn(e, element));
-
-  /// Same as [contains] but uses [identical] to compare the objects
-  bool containsIdentical(T element) =>
-      containsIf(element, (a, b) => identical(a, b));
-
-  Map<U, List<T>> groupBy<U>({required U Function(T e) key}) {
-    return fold<Map<U, List<T>>>(
-        {},
-        (previousValue, element) =>
-            previousValue..putIfAbsent(key(element), () => []).add(element));
-  }
-
-  /// Return a new list with only distinct elements
-  List<T> distinct() {
-    final s = <T>{};
-    return where((element) => s.add(element)).toList();
-  }
-
-  /// Return a new list with only distinct elements determined by [equalFn]
-  List<T> distinctIf(
-      bool Function(T a, T b) equalFn, int Function(T a) hashCodeFn) {
-    final s = <OverrideComparator<T>>{};
-    return where((element) =>
-        s.add(OverrideComparator<T>(element, equalFn, hashCodeFn))).toList();
-  }
-
-  /// Invokes [action] on each element of this iterable in iteration order
-  /// lazily
-  Iterable<T> forEachLazy(void Function(T element) action) sync* {
-    for (final e in this) {
-      action(e);
-      yield e;
-    }
-  }
-
   Future<List<U>> computeAll<U>(ComputeCallback<T, U> callback) async {
     final list = asList();
     if (list.isEmpty) {
@@ -66,63 +13,6 @@ extension IterableExtension<T> on Iterable<T> {
           _computeAllImpl<T, U>, _ComputeAllMessage(callback, list));
     }
   }
-
-  /// Return a list containing elements in this iterable
-  ///
-  /// If this Iterable is itself a list, this will be returned directly with no
-  /// copying
-  List<T> asList() {
-    if (this is List) {
-      return this as List<T>;
-    } else {
-      return toList();
-    }
-  }
-
-  /// The first index of [element] in this iterable
-  ///
-  /// Searches the list from index start to the end of the list. The first time
-  /// an object o is encountered so that o == element, the index of o is
-  /// returned. Returns -1 if element is not found.
-  int indexOf(T element, [int start = 0]) {
-    var i = 0;
-    for (final e in this) {
-      final j = i++;
-      if (j < start) {
-        continue;
-      }
-      if (e == element) {
-        return j;
-      }
-    }
-    return -1;
-  }
-
-  Future<List<U>> withPartition<U>(
-      FutureOr<Iterable<U>> Function(Iterable<T> sublist) fn, int size) async {
-    final products = <U>[];
-    final sublists = partition(this, size);
-    for (final l in sublists) {
-      products.addAll(await fn(l));
-    }
-    return products;
-  }
-
-  Future<void> withPartitionNoReturn(
-      FutureOr<void> Function(Iterable<T> sublist) fn, int size) async {
-    final sublists = partition(this, size);
-    for (final l in sublists) {
-      await fn(l);
-    }
-  }
-}
-
-extension IterableFlattenExtension<T> on Iterable<Iterable<T>> {
-  /// Flattens an [Iterable] of [Iterable] values of type [T] to a [Iterable] of
-  /// values of type [T].
-  ///
-  /// This function originated in the xml package
-  Iterable<T> flatten() => expand((values) => values);
 }
 
 class _ComputeAllMessage<T, U> {
diff --git a/app/lib/legacy/sign_in.dart b/app/lib/legacy/sign_in.dart
index f543ee28..dadc6954 100644
--- a/app/lib/legacy/sign_in.dart
+++ b/app/lib/legacy/sign_in.dart
@@ -10,7 +10,6 @@ import 'package:nc_photos/entity/pref.dart';
 import 'package:nc_photos/entity/pref_util.dart' as pref_util;
 import 'package:nc_photos/entity/sqlite/database.dart' as sql;
 import 'package:nc_photos/help_utils.dart' as help_utils;
-import 'package:nc_photos/iterable_extension.dart';
 import 'package:nc_photos/legacy/connect.dart';
 import 'package:nc_photos/platform/k.dart' as platform_k;
 import 'package:nc_photos/theme.dart';
@@ -18,6 +17,7 @@ import 'package:nc_photos/url_launcher_util.dart';
 import 'package:nc_photos/widget/home.dart';
 import 'package:nc_photos/widget/root_picker.dart';
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 import 'package:np_string/np_string.dart';
 
 part 'sign_in.g.dart';
diff --git a/app/lib/suggester.dart b/app/lib/suggester.dart
index b415ccb5..b82a3a44 100644
--- a/app/lib/suggester.dart
+++ b/app/lib/suggester.dart
@@ -1,8 +1,8 @@
 import 'package:collection/collection.dart';
 import 'package:flutter/foundation.dart';
 import 'package:logging/logging.dart';
-import 'package:nc_photos/iterable_extension.dart';
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 import 'package:np_string/np_string.dart';
 import 'package:tuple/tuple.dart';
 import 'package:woozy_search/woozy_search.dart';
diff --git a/app/lib/use_case/album/remove_from_album.dart b/app/lib/use_case/album/remove_from_album.dart
index cf8deb56..9716af59 100644
--- a/app/lib/use_case/album/remove_from_album.dart
+++ b/app/lib/use_case/album/remove_from_album.dart
@@ -9,12 +9,12 @@ import 'package:nc_photos/entity/album/provider.dart';
 import 'package:nc_photos/entity/file.dart';
 import 'package:nc_photos/entity/file_descriptor.dart';
 import 'package:nc_photos/exception.dart';
-import 'package:nc_photos/iterable_extension.dart';
 import 'package:nc_photos/use_case/album/unshare_file_from_album.dart';
 import 'package:nc_photos/use_case/preprocess_album.dart';
 import 'package:nc_photos/use_case/update_album.dart';
 import 'package:nc_photos/use_case/update_album_with_actual_items.dart';
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 import 'package:np_common/type.dart';
 
 part 'remove_from_album.g.dart';
diff --git a/app/lib/use_case/album/share_album_with_user.dart b/app/lib/use_case/album/share_album_with_user.dart
index f2d0af20..484440a7 100644
--- a/app/lib/use_case/album/share_album_with_user.dart
+++ b/app/lib/use_case/album/share_album_with_user.dart
@@ -7,10 +7,10 @@ import 'package:nc_photos/entity/album/provider.dart';
 import 'package:nc_photos/entity/file.dart';
 import 'package:nc_photos/entity/share.dart';
 import 'package:nc_photos/entity/sharee.dart';
-import 'package:nc_photos/iterable_extension.dart';
 import 'package:nc_photos/use_case/create_share.dart';
 import 'package:nc_photos/use_case/update_album.dart';
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 import 'package:np_common/or_null.dart';
 import 'package:np_common/type.dart';
 import 'package:np_string/np_string.dart';
diff --git a/app/lib/use_case/cache_favorite.dart b/app/lib/use_case/cache_favorite.dart
index fff59516..f9c10174 100644
--- a/app/lib/use_case/cache_favorite.dart
+++ b/app/lib/use_case/cache_favorite.dart
@@ -8,10 +8,9 @@ import 'package:nc_photos/di_container.dart';
 import 'package:nc_photos/entity/sqlite/database.dart' as sql;
 import 'package:nc_photos/entity/sqlite/files_query_builder.dart' as sql;
 import 'package:nc_photos/event/event.dart';
-import 'package:nc_photos/iterable_extension.dart';
-import 'package:nc_photos/list_util.dart' as list_util;
 import 'package:nc_photos/object_extension.dart';
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 
 part 'cache_favorite.g.dart';
 
@@ -32,8 +31,7 @@ class CacheFavorite {
       final cache = await _getCacheFavorites(db, dbAccount);
       final cacheMap =
           Map.fromEntries(cache.map((e) => MapEntry(e.fileId, e.rowId)));
-      final diff =
-          list_util.diff(cacheMap.keys.sorted(Comparable.compare), remote);
+      final diff = getDiff(cacheMap.keys.sorted(Comparable.compare), remote);
       final newFileIds = diff.onlyInB;
       _log.info("[call] New favorites: ${newFileIds.toReadableString()}");
       final removedFildIds = diff.onlyInA;
diff --git a/app/lib/use_case/compat/v55.dart b/app/lib/use_case/compat/v55.dart
index bd014f6a..6dc04906 100644
--- a/app/lib/use_case/compat/v55.dart
+++ b/app/lib/use_case/compat/v55.dart
@@ -3,8 +3,8 @@ import 'package:flutter/foundation.dart';
 import 'package:logging/logging.dart';
 import 'package:nc_photos/entity/file_util.dart' as file_util;
 import 'package:nc_photos/entity/sqlite/database.dart' as sql;
-import 'package:nc_photos/iterable_extension.dart';
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 import 'package:tuple/tuple.dart';
 
 part 'v55.g.dart';
diff --git a/app/lib/use_case/face_recognition_person/sync_face_recognition_person.dart b/app/lib/use_case/face_recognition_person/sync_face_recognition_person.dart
index a6ea2073..4b20c2e9 100644
--- a/app/lib/use_case/face_recognition_person/sync_face_recognition_person.dart
+++ b/app/lib/use_case/face_recognition_person/sync_face_recognition_person.dart
@@ -7,10 +7,9 @@ import 'package:nc_photos/entity/face_recognition_person.dart';
 import 'package:nc_photos/entity/sqlite/database.dart' as sql;
 import 'package:nc_photos/entity/sqlite/type_converter.dart';
 import 'package:nc_photos/exception.dart';
-import 'package:nc_photos/iterable_extension.dart';
-import 'package:nc_photos/list_util.dart' as list_util;
 import 'package:nc_photos/use_case/face_recognition_person/list_face_recognition_person.dart';
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 
 part 'sync_face_recognition_person.g.dart';
 
@@ -41,7 +40,7 @@ class SyncFaceRecognitionPerson {
     final cache = (await ListFaceRecognitionPerson(_c.withLocalRepo())(account)
         .last)
       ..sort(personSorter);
-    final diff = list_util.diffWith(cache, remote, personSorter);
+    final diff = getDiffWith(cache, remote, personSorter);
     final inserts = diff.onlyInB;
     _log.info("[call] New people: ${inserts.toReadableString()}");
     final deletes = diff.onlyInA;
diff --git a/app/lib/use_case/find_file.dart b/app/lib/use_case/find_file.dart
index 7d462f47..d3e3d4c9 100644
--- a/app/lib/use_case/find_file.dart
+++ b/app/lib/use_case/find_file.dart
@@ -3,8 +3,8 @@ import 'package:nc_photos/account.dart';
 import 'package:nc_photos/di_container.dart';
 import 'package:nc_photos/entity/file.dart';
 import 'package:nc_photos/entity/sqlite/database.dart' as sql;
-import 'package:nc_photos/iterable_extension.dart';
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 
 part 'find_file.g.dart';
 
diff --git a/app/lib/use_case/find_file_descriptor.dart b/app/lib/use_case/find_file_descriptor.dart
index 559110f8..47f9b3f8 100644
--- a/app/lib/use_case/find_file_descriptor.dart
+++ b/app/lib/use_case/find_file_descriptor.dart
@@ -3,8 +3,8 @@ import 'package:nc_photos/account.dart';
 import 'package:nc_photos/di_container.dart';
 import 'package:nc_photos/entity/file_descriptor.dart';
 import 'package:nc_photos/entity/sqlite/database.dart' as sql;
-import 'package:nc_photos/iterable_extension.dart';
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 
 part 'find_file_descriptor.g.dart';
 
diff --git a/app/lib/use_case/recognize_face/sync_recognize_face.dart b/app/lib/use_case/recognize_face/sync_recognize_face.dart
index d28a1a0a..28484c8f 100644
--- a/app/lib/use_case/recognize_face/sync_recognize_face.dart
+++ b/app/lib/use_case/recognize_face/sync_recognize_face.dart
@@ -8,12 +8,10 @@ import 'package:nc_photos/entity/recognize_face_item.dart';
 import 'package:nc_photos/entity/sqlite/database.dart' as sql;
 import 'package:nc_photos/entity/sqlite/type_converter.dart';
 import 'package:nc_photos/exception.dart';
-import 'package:nc_photos/iterable_extension.dart';
-import 'package:nc_photos/list_util.dart' as list_util;
-import 'package:nc_photos/map_extension.dart';
 import 'package:nc_photos/use_case/recognize_face/list_recognize_face.dart';
 import 'package:nc_photos/use_case/recognize_face/list_recognize_face_item.dart';
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 
 part 'sync_recognize_face.g.dart';
 
@@ -96,7 +94,7 @@ class SyncRecognizeFace {
     }
     final cache = (await ListRecognizeFace(_c.withLocalRepo())(account).last)
       ..sort(faceSorter);
-    final diff = list_util.diffWith(cache, remote, faceSorter);
+    final diff = getDiffWith(cache, remote, faceSorter);
     final inserts = diff.onlyInB;
     _log.info("[_getFaceResults] New face: ${inserts.toReadableString()}");
     final deletes = diff.onlyInA;
@@ -152,8 +150,8 @@ class SyncRecognizeFace {
     for (final f in faces) {
       final thisCache = (cache[f] ?? [])..sort(itemSorter);
       final thisRemote = (remote[f] ?? [])..sort(itemSorter);
-      final diff = list_util.diffWith<RecognizeFaceItem>(
-          thisCache, thisRemote, itemSorter);
+      final diff =
+          getDiffWith<RecognizeFaceItem>(thisCache, thisRemote, itemSorter);
       final inserts = diff.onlyInB;
       _log.info(
           "[_getFaceItemResults] New item: ${inserts.toReadableString()}");
@@ -194,7 +192,7 @@ class SyncRecognizeFace {
   //       await ListRecognizeFaceItem(_c.withLocalRepo())(account, face).last;
   //   int itemSorter(RecognizeFaceItem a, RecognizeFaceItem b) =>
   //       a.fileId.compareTo(b.fileId);
-  //   final diff = list_util.diffWith(cache, remote, itemSorter);
+  //   final diff = getDiffWith(cache, remote, itemSorter);
   //   final inserts = diff.onlyInB;
   //   _log.info("[_getFaceItemResults] New face: ${inserts.toReadableString()}");
   //   final deletes = diff.onlyInA;
diff --git a/app/lib/use_case/remove.dart b/app/lib/use_case/remove.dart
index 131728ee..0b0ab87b 100644
--- a/app/lib/use_case/remove.dart
+++ b/app/lib/use_case/remove.dart
@@ -10,13 +10,13 @@ import 'package:nc_photos/entity/album/provider.dart';
 import 'package:nc_photos/entity/file.dart';
 import 'package:nc_photos/entity/file_descriptor.dart';
 import 'package:nc_photos/event/event.dart';
-import 'package:nc_photos/iterable_extension.dart';
 import 'package:nc_photos/stream_extension.dart';
 import 'package:nc_photos/use_case/album/list_album.dart';
 import 'package:nc_photos/use_case/album/remove_from_album.dart';
 import 'package:nc_photos/use_case/list_share.dart';
 import 'package:nc_photos/use_case/remove_share.dart';
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 import 'package:np_common/type.dart';
 import 'package:np_string/np_string.dart';
 
diff --git a/app/lib/use_case/sync_tag.dart b/app/lib/use_case/sync_tag.dart
index 3358348f..0efab95e 100644
--- a/app/lib/use_case/sync_tag.dart
+++ b/app/lib/use_case/sync_tag.dart
@@ -6,9 +6,8 @@ import 'package:nc_photos/di_container.dart';
 import 'package:nc_photos/entity/sqlite/database.dart' as sql;
 import 'package:nc_photos/entity/sqlite/type_converter.dart';
 import 'package:nc_photos/entity/tag.dart';
-import 'package:nc_photos/iterable_extension.dart';
-import 'package:nc_photos/list_util.dart' as list_util;
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 
 part 'sync_tag.g.dart';
 
@@ -26,7 +25,7 @@ class SyncTag {
     int tagSorter(Tag a, Tag b) => a.id.compareTo(b.id);
     final remote = (await _c.tagRepoRemote.list(account))..sort(tagSorter);
     final cache = (await _c.tagRepoLocal.list(account))..sort(tagSorter);
-    final diff = list_util.diffWith<Tag>(cache, remote, tagSorter);
+    final diff = getDiffWith<Tag>(cache, remote, tagSorter);
     final inserts = diff.onlyInB;
     _log.info("[call] New tags: ${inserts.toReadableString()}");
     final deletes = diff.onlyInA;
diff --git a/app/lib/widget/album_dir_picker.dart b/app/lib/widget/album_dir_picker.dart
index e4b8de93..700ca82e 100644
--- a/app/lib/widget/album_dir_picker.dart
+++ b/app/lib/widget/album_dir_picker.dart
@@ -5,11 +5,11 @@ import 'package:nc_photos/api/api_util.dart' as api_util;
 import 'package:nc_photos/app_localizations.dart';
 import 'package:nc_photos/entity/file.dart';
 import 'package:nc_photos/entity/file_descriptor.dart';
-import 'package:nc_photos/iterable_extension.dart';
 import 'package:nc_photos/k.dart' as k;
 import 'package:nc_photos/snack_bar_manager.dart';
 import 'package:nc_photos/widget/dir_picker.dart';
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 
 part 'album_dir_picker.g.dart';
 
diff --git a/app/lib/widget/album_importer.dart b/app/lib/widget/album_importer.dart
index fa54e10c..7a7e9112 100644
--- a/app/lib/widget/album_importer.dart
+++ b/app/lib/widget/album_importer.dart
@@ -17,7 +17,6 @@ import 'package:nc_photos/entity/file.dart';
 import 'package:nc_photos/entity/file_descriptor.dart';
 import 'package:nc_photos/entity/file_util.dart' as file_util;
 import 'package:nc_photos/exception_util.dart' as exception_util;
-import 'package:nc_photos/iterable_extension.dart';
 import 'package:nc_photos/k.dart' as k;
 import 'package:nc_photos/snack_bar_manager.dart';
 import 'package:nc_photos/use_case/album/create_album.dart';
@@ -25,6 +24,7 @@ import 'package:nc_photos/use_case/preprocess_album.dart';
 import 'package:nc_photos/use_case/update_album_with_actual_items.dart';
 import 'package:nc_photos/widget/processing_dialog.dart';
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 
 part 'album_importer.g.dart';
 
diff --git a/app/lib/widget/enhanced_photo_browser.dart b/app/lib/widget/enhanced_photo_browser.dart
index 0eb64ee8..81d63597 100644
--- a/app/lib/widget/enhanced_photo_browser.dart
+++ b/app/lib/widget/enhanced_photo_browser.dart
@@ -11,7 +11,6 @@ import 'package:nc_photos/entity/file_util.dart' as file_util;
 import 'package:nc_photos/entity/local_file.dart';
 import 'package:nc_photos/entity/pref.dart';
 import 'package:nc_photos/exception_util.dart' as exception_util;
-import 'package:nc_photos/iterable_extension.dart';
 import 'package:nc_photos/k.dart' as k;
 import 'package:nc_photos/mobile/android/android_info.dart';
 import 'package:nc_photos/mobile/android/permission_util.dart';
@@ -28,6 +27,7 @@ import 'package:nc_photos/widget/selectable_item_stream_list_mixin.dart';
 import 'package:nc_photos/widget/selection_app_bar.dart';
 import 'package:nc_photos_plugin/nc_photos_plugin.dart';
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 
 part 'enhanced_photo_browser.g.dart';
 
diff --git a/app/lib/widget/file_sharer_dialog.dart b/app/lib/widget/file_sharer_dialog.dart
index 26402d53..085cc572 100644
--- a/app/lib/widget/file_sharer_dialog.dart
+++ b/app/lib/widget/file_sharer_dialog.dart
@@ -17,7 +17,6 @@ import 'package:nc_photos/entity/file_descriptor.dart';
 import 'package:nc_photos/entity/file_util.dart' as file_util;
 import 'package:nc_photos/exception_event.dart';
 import 'package:nc_photos/exception_util.dart' as exception_util;
-import 'package:nc_photos/iterable_extension.dart';
 import 'package:nc_photos/k.dart' as k;
 import 'package:nc_photos/mobile/share.dart';
 import 'package:nc_photos/platform/k.dart' as platform_k;
@@ -34,6 +33,7 @@ import 'package:nc_photos/widget/share_link_multiple_files_dialog.dart';
 import 'package:nc_photos/widget/simple_input_dialog.dart';
 import 'package:nc_photos_plugin/nc_photos_plugin.dart';
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 import 'package:to_string/to_string.dart';
 import 'package:tuple/tuple.dart';
 
diff --git a/app/lib/widget/image_editor/color_toolbar.dart b/app/lib/widget/image_editor/color_toolbar.dart
index 31b9cc56..3cdab079 100644
--- a/app/lib/widget/image_editor/color_toolbar.dart
+++ b/app/lib/widget/image_editor/color_toolbar.dart
@@ -1,9 +1,9 @@
 import 'package:flutter/material.dart';
 import 'package:nc_photos/app_localizations.dart';
-import 'package:nc_photos/iterable_extension.dart';
 import 'package:nc_photos/object_extension.dart';
 import 'package:nc_photos/widget/image_editor/toolbar_button.dart';
 import 'package:nc_photos_plugin/nc_photos_plugin.dart';
+import 'package:np_collection/np_collection.dart';
 import 'package:np_string/np_string.dart';
 import 'package:np_ui/np_ui.dart';
 
diff --git a/app/lib/widget/selectable_item_list.dart b/app/lib/widget/selectable_item_list.dart
index 05413984..9967080e 100644
--- a/app/lib/widget/selectable_item_list.dart
+++ b/app/lib/widget/selectable_item_list.dart
@@ -5,13 +5,13 @@ import 'package:flutter/material.dart';
 import 'package:flutter_staggered_grid_view/flutter_staggered_grid_view.dart';
 import 'package:logging/logging.dart';
 import 'package:nc_photos/app_localizations.dart';
-import 'package:nc_photos/iterable_extension.dart';
 import 'package:nc_photos/k.dart' as k;
 import 'package:nc_photos/platform/k.dart' as platform_k;
 import 'package:nc_photos/session_storage.dart';
 import 'package:nc_photos/snack_bar_manager.dart';
 import 'package:nc_photos/widget/selectable.dart';
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 
 part 'selectable_item_list.g.dart';
 
diff --git a/app/lib/widget/selectable_item_stream_list_mixin.dart b/app/lib/widget/selectable_item_stream_list_mixin.dart
index a983e5de..cf5dbbd7 100644
--- a/app/lib/widget/selectable_item_stream_list_mixin.dart
+++ b/app/lib/widget/selectable_item_stream_list_mixin.dart
@@ -5,7 +5,6 @@ import 'package:flutter/material.dart';
 import 'package:flutter_staggered_grid_view/flutter_staggered_grid_view.dart';
 import 'package:logging/logging.dart';
 import 'package:nc_photos/app_localizations.dart';
-import 'package:nc_photos/iterable_extension.dart';
 import 'package:nc_photos/k.dart' as k;
 import 'package:nc_photos/platform/k.dart' as platform_k;
 import 'package:nc_photos/session_storage.dart';
@@ -13,6 +12,7 @@ import 'package:nc_photos/snack_bar_manager.dart';
 import 'package:nc_photos/widget/measurable_item_list.dart';
 import 'package:nc_photos/widget/selectable.dart';
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 import 'package:uuid/uuid.dart';
 import 'package:visibility_detector/visibility_detector.dart';
 
diff --git a/app/lib/widget/share_folder_picker.dart b/app/lib/widget/share_folder_picker.dart
index 5818c617..845df6bf 100644
--- a/app/lib/widget/share_folder_picker.dart
+++ b/app/lib/widget/share_folder_picker.dart
@@ -5,11 +5,11 @@ import 'package:nc_photos/app_localizations.dart';
 import 'package:nc_photos/entity/file.dart';
 import 'package:nc_photos/entity/file_descriptor.dart';
 import 'package:nc_photos/entity/file_util.dart' as file_util;
-import 'package:nc_photos/iterable_extension.dart';
 import 'package:nc_photos/k.dart' as k;
 import 'package:nc_photos/snack_bar_manager.dart';
 import 'package:nc_photos/widget/dir_picker.dart';
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 
 part 'share_folder_picker.g.dart';
 
diff --git a/app/lib/widget/sign_in.dart b/app/lib/widget/sign_in.dart
index a809ddb9..402c0e63 100644
--- a/app/lib/widget/sign_in.dart
+++ b/app/lib/widget/sign_in.dart
@@ -10,13 +10,13 @@ import 'package:nc_photos/di_container.dart';
 import 'package:nc_photos/entity/pref.dart';
 import 'package:nc_photos/entity/pref_util.dart' as pref_util;
 import 'package:nc_photos/entity/sqlite/database.dart' as sql;
-import 'package:nc_photos/iterable_extension.dart';
 import 'package:nc_photos/legacy/sign_in.dart' as legacy;
 import 'package:nc_photos/theme.dart';
 import 'package:nc_photos/widget/connect.dart';
 import 'package:nc_photos/widget/home.dart';
 import 'package:nc_photos/widget/root_picker.dart';
 import 'package:np_codegen/np_codegen.dart';
+import 'package:np_collection/np_collection.dart';
 import 'package:np_string/np_string.dart';
 
 part 'sign_in.g.dart';
diff --git a/app/pubspec.lock b/app/pubspec.lock
index 96f18380..9c519f4e 100644
--- a/app/pubspec.lock
+++ b/app/pubspec.lock
@@ -962,6 +962,13 @@ packages:
       relative: true
     source: path
     version: "1.0.0"
+  np_collection:
+    dependency: "direct main"
+    description:
+      path: "../np_collection"
+      relative: true
+    source: path
+    version: "1.0.0"
   np_common:
     dependency: "direct main"
     description:
@@ -1205,7 +1212,7 @@ packages:
     source: hosted
     version: "1.2.3"
   quiver:
-    dependency: "direct main"
+    dependency: transitive
     description:
       name: quiver
       sha256: b1c1ac5ce6688d77f65f3375a9abb9319b3cb32486bdc7a1e0fdf004d7ba4e47
diff --git a/app/pubspec.yaml b/app/pubspec.yaml
index 79650acc..c3fbd18d 100644
--- a/app/pubspec.yaml
+++ b/app/pubspec.yaml
@@ -103,6 +103,8 @@ dependencies:
     path: ../codegen
   np_common:
     path: ../np_common
+  np_collection:
+    path: ../np_collection
   np_log:
     path: ../np_log
   np_math:
@@ -115,7 +117,6 @@ dependencies:
   page_view_indicators: ^2.0.0
   path: ^1.8.0
   path_provider: ^2.0.15
-  quiver: ^3.2.1
   rxdart: ^0.27.7
   screen_brightness:  ^0.2.2
   shared_preferences: ^2.0.8
diff --git a/app/test/entity/file/data_source_test.dart b/app/test/entity/file/data_source_test.dart
index 57114ff2..fc49820b 100644
--- a/app/test/entity/file/data_source_test.dart
+++ b/app/test/entity/file/data_source_test.dart
@@ -2,7 +2,7 @@ import 'package:nc_photos/di_container.dart';
 import 'package:nc_photos/entity/file.dart';
 import 'package:nc_photos/entity/file/data_source.dart';
 import 'package:nc_photos/entity/sqlite/database.dart' as sql;
-import 'package:nc_photos/list_extension.dart';
+import 'package:np_collection/np_collection.dart';
 import 'package:np_common/or_null.dart';
 import 'package:test/test.dart';
 
diff --git a/app/test/entity/file/file_cache_manager_test.dart b/app/test/entity/file/file_cache_manager_test.dart
index 07b3d7d5..5d97d0ce 100644
--- a/app/test/entity/file/file_cache_manager_test.dart
+++ b/app/test/entity/file/file_cache_manager_test.dart
@@ -3,7 +3,7 @@ import 'package:nc_photos/entity/file.dart';
 import 'package:nc_photos/entity/file/data_source.dart';
 import 'package:nc_photos/entity/file/file_cache_manager.dart';
 import 'package:nc_photos/entity/sqlite/database.dart' as sql;
-import 'package:nc_photos/list_extension.dart';
+import 'package:np_collection/np_collection.dart';
 import 'package:np_common/or_null.dart';
 import 'package:np_math/np_math.dart';
 import 'package:test/test.dart';
diff --git a/app/test/test_util.dart b/app/test/test_util.dart
index ea1f186b..2f21ea2b 100644
--- a/app/test/test_util.dart
+++ b/app/test/test_util.dart
@@ -16,7 +16,7 @@ import 'package:nc_photos/entity/share.dart';
 import 'package:nc_photos/entity/sharee.dart';
 import 'package:nc_photos/entity/sqlite/database.dart' as sql;
 import 'package:nc_photos/entity/sqlite/type_converter.dart';
-import 'package:nc_photos/iterable_extension.dart';
+import 'package:np_collection/np_collection.dart';
 import 'package:np_common/or_null.dart';
 import 'package:np_string/np_string.dart';
 import 'package:tuple/tuple.dart';
diff --git a/app/test/use_case/inflate_file_descriptor_test.dart b/app/test/use_case/inflate_file_descriptor_test.dart
index 2e409ad7..3c679f15 100644
--- a/app/test/use_case/inflate_file_descriptor_test.dart
+++ b/app/test/use_case/inflate_file_descriptor_test.dart
@@ -2,8 +2,8 @@ import 'package:clock/clock.dart';
 import 'package:nc_photos/di_container.dart';
 import 'package:nc_photos/entity/file_descriptor.dart';
 import 'package:nc_photos/entity/sqlite/database.dart' as sql;
-import 'package:nc_photos/list_extension.dart';
 import 'package:nc_photos/use_case/inflate_file_descriptor.dart';
+import 'package:np_collection/np_collection.dart';
 import 'package:test/test.dart';
 
 import '../test_util.dart' as util;
diff --git a/app/test/use_case/ls_test.dart b/app/test/use_case/ls_test.dart
index 1be9698b..da53367a 100644
--- a/app/test/use_case/ls_test.dart
+++ b/app/test/use_case/ls_test.dart
@@ -1,7 +1,7 @@
 import 'package:nc_photos/entity/file.dart';
 import 'package:nc_photos/entity/file_util.dart' as file_util;
-import 'package:nc_photos/list_extension.dart';
 import 'package:nc_photos/use_case/ls.dart';
+import 'package:np_collection/np_collection.dart';
 import 'package:test/test.dart';
 
 import '../mock_type.dart';
diff --git a/np_collection/.gitignore b/np_collection/.gitignore
new file mode 100644
index 00000000..3cceda55
--- /dev/null
+++ b/np_collection/.gitignore
@@ -0,0 +1,7 @@
+# https://dart.dev/guides/libraries/private-files
+# Created by `dart pub`
+.dart_tool/
+
+# Avoid committing pubspec.lock for library packages; see
+# https://dart.dev/guides/libraries/private-files#pubspeclock.
+pubspec.lock
diff --git a/np_collection/analysis_options.yaml b/np_collection/analysis_options.yaml
new file mode 100644
index 00000000..f92d2567
--- /dev/null
+++ b/np_collection/analysis_options.yaml
@@ -0,0 +1 @@
+include: package:np_lints/np.yaml
diff --git a/np_collection/lib/np_collection.dart b/np_collection/lib/np_collection.dart
new file mode 100644
index 00000000..d3fff8b0
--- /dev/null
+++ b/np_collection/lib/np_collection.dart
@@ -0,0 +1,7 @@
+library np_collection;
+
+export 'src/iterable_extension.dart';
+export 'src/iterator_extension.dart';
+export 'src/list_extension.dart';
+export 'src/list_util.dart';
+export 'src/map_extension.dart';
diff --git a/np_collection/lib/src/iterable_extension.dart b/np_collection/lib/src/iterable_extension.dart
new file mode 100644
index 00000000..72bf6a0c
--- /dev/null
+++ b/np_collection/lib/src/iterable_extension.dart
@@ -0,0 +1,114 @@
+import 'dart:async';
+import 'dart:collection';
+
+import 'package:collection/collection.dart';
+import 'package:np_collection/src/list_extension.dart';
+import 'package:quiver/iterables.dart';
+import 'package:tuple/tuple.dart';
+
+extension IterableExtension<T> on Iterable<T> {
+  /// Return a new stable sorted list
+  List<T> stableSorted([int Function(T a, T b)? compare]) =>
+      toList()..stableSort(compare);
+
+  /// Return a string representation of this iterable by joining the result of
+  /// toString for each items
+  String toReadableString() => "[${join(', ')}]";
+
+  Iterable<Tuple2<int, T>> withIndex() => mapIndexed((i, e) => Tuple2(i, e));
+
+  /// Whether the collection contains an element equal to [element] using the
+  /// equality function [equalFn]
+  bool containsIf(T element, bool Function(T a, T b) equalFn) =>
+      any((e) => equalFn(e, element));
+
+  /// Same as [contains] but uses [identical] to compare the objects
+  bool containsIdentical(T element) =>
+      containsIf(element, (a, b) => identical(a, b));
+
+  Map<U, List<T>> groupBy<U>({required U Function(T e) key}) {
+    return fold<Map<U, List<T>>>(
+        {},
+        (previousValue, element) =>
+            previousValue..putIfAbsent(key(element), () => []).add(element));
+  }
+
+  /// Return a new list with only distinct elements
+  List<T> distinct() {
+    final s = <T>{};
+    return where((element) => s.add(element)).toList();
+  }
+
+  /// Return a new list with only distinct elements determined by [equalFn]
+  List<T> distinctIf(
+      bool Function(T a, T b) equalFn, int Function(T a) hashCodeFn) {
+    final s = LinkedHashSet(equals: equalFn, hashCode: hashCodeFn);
+    return where((element) => s.add(element)).toList();
+  }
+
+  /// Invokes [action] on each element of this iterable in iteration order
+  /// lazily
+  Iterable<T> forEachLazy(void Function(T element) action) sync* {
+    for (final e in this) {
+      action(e);
+      yield e;
+    }
+  }
+
+  /// Return a list containing elements in this iterable
+  ///
+  /// If this Iterable is itself a list, this will be returned directly with no
+  /// copying
+  List<T> asList() {
+    if (this is List) {
+      return this as List<T>;
+    } else {
+      return toList();
+    }
+  }
+
+  /// The first index of [element] in this iterable
+  ///
+  /// Searches the list from index start to the end of the list. The first time
+  /// an object o is encountered so that o == element, the index of o is
+  /// returned. Returns -1 if element is not found.
+  int indexOf(T element, [int start = 0]) {
+    var i = 0;
+    for (final e in this) {
+      final j = i++;
+      if (j < start) {
+        continue;
+      }
+      if (e == element) {
+        return j;
+      }
+    }
+    return -1;
+  }
+
+  Future<List<U>> withPartition<U>(
+      FutureOr<Iterable<U>> Function(Iterable<T> sublist) fn, int size) async {
+    final products = <U>[];
+    final sublists = partition(this, size);
+    for (final l in sublists) {
+      products.addAll(await fn(l));
+    }
+    return products;
+  }
+
+  Future<void> withPartitionNoReturn(
+      FutureOr<void> Function(Iterable<T> sublist) fn, int size) async {
+    final sublists = partition(this, size);
+    for (final l in sublists) {
+      await fn(l);
+    }
+  }
+}
+
+extension IterableFlattenExtension<T> on Iterable<Iterable<T>> {
+  /// Flattens an [Iterable] of [Iterable] values of type [T] to a [Iterable] of
+  /// values of type [T].
+  ///
+  /// This function originated in the xml package
+  Iterable<T> flatten() => expand((values) => values);
+}
diff --git a/app/lib/iterator_extension.dart b/np_collection/lib/src/iterator_extension.dart
similarity index 100%
rename from app/lib/iterator_extension.dart
rename to np_collection/lib/src/iterator_extension.dart
diff --git a/app/lib/list_extension.dart b/np_collection/lib/src/list_extension.dart
similarity index 100%
rename from app/lib/list_extension.dart
rename to np_collection/lib/src/list_extension.dart
diff --git a/app/lib/list_util.dart b/np_collection/lib/src/list_util.dart
similarity index 90%
rename from app/lib/list_util.dart
rename to np_collection/lib/src/list_util.dart
index 3e992e23..3266afce 100644
--- a/app/lib/list_util.dart
+++ b/np_collection/lib/src/list_util.dart
@@ -1,4 +1,4 @@
-import 'package:nc_photos/iterator_extension.dart';
+import 'package:np_collection/src/iterator_extension.dart';
 
 /// Contain results from the diff functions
 ///
@@ -18,7 +18,7 @@ class DiffResult<T> {
 ///
 /// [a] and [b] MUST be sorted in ascending order, otherwise the result is
 /// undefined
-DiffResult<T> diffWith<T>(
+DiffResult<T> getDiffWith<T>(
     Iterable<T> a, Iterable<T> b, int Function(T a, T b) comparator) {
   final aIt = a.iterator, bIt = b.iterator;
   final aMissing = <T>[], bMissing = <T>[];
@@ -41,8 +41,8 @@ DiffResult<T> diffWith<T>(
   }
 }
 
-DiffResult<T> diff<T extends Comparable>(Iterable<T> a, Iterable<T> b) =>
-    diffWith(a, b, Comparable.compare);
+DiffResult<T> getDiff<T extends Comparable>(Iterable<T> a, Iterable<T> b) =>
+    getDiffWith(a, b, Comparable.compare);
 
 DiffResult<T> _diffUntilEqual<T>(
     Iterator<T> aIt, Iterator<T> bIt, int Function(T a, T b) comparator) {
diff --git a/app/lib/map_extension.dart b/np_collection/lib/src/map_extension.dart
similarity index 100%
rename from app/lib/map_extension.dart
rename to np_collection/lib/src/map_extension.dart
diff --git a/np_collection/pubspec.yaml b/np_collection/pubspec.yaml
new file mode 100644
index 00000000..6ebb1f78
--- /dev/null
+++ b/np_collection/pubspec.yaml
@@ -0,0 +1,20 @@
+name: np_collection
+description: A starting point for Dart libraries or applications.
+version: 1.0.0
+# repository: https://github.com/my_org/my_repo
+publish_to: none
+
+environment:
+  sdk: '>=2.19.6 <3.0.0'
+
+dependencies:
+  collection: ^1.15.0
+  np_math:
+    path: ../np_math
+  quiver: ^3.2.1
+  tuple: ^2.0.1
+
+dev_dependencies:
+  np_lints:
+    path: ../np_lints
+  test: ^1.21.0
diff --git a/app/test/iterable_extension_test.dart b/np_collection/test/iterable_extension_test.dart
similarity index 98%
rename from app/test/iterable_extension_test.dart
rename to np_collection/test/iterable_extension_test.dart
index c94cb705..4cfea48c 100644
--- a/app/test/iterable_extension_test.dart
+++ b/np_collection/test/iterable_extension_test.dart
@@ -1,4 +1,4 @@
-import 'package:nc_photos/iterable_extension.dart';
+import 'package:np_collection/src/iterable_extension.dart';
 import 'package:np_math/np_math.dart';
 import 'package:quiver/core.dart';
 import 'package:test/test.dart';
diff --git a/app/test/iterator_extension_test.dart b/np_collection/test/iterator_extension_test.dart
similarity index 88%
rename from app/test/iterator_extension_test.dart
rename to np_collection/test/iterator_extension_test.dart
index 85f883ab..19cac71f 100644
--- a/app/test/iterator_extension_test.dart
+++ b/np_collection/test/iterator_extension_test.dart
@@ -1,4 +1,4 @@
-import 'package:nc_photos/iterator_extension.dart';
+import 'package:np_collection/src/iterator_extension.dart';
 import 'package:test/test.dart';
 
 void main() {
diff --git a/app/test/list_extension_test.dart b/np_collection/test/list_extension_test.dart
similarity index 97%
rename from app/test/list_extension_test.dart
rename to np_collection/test/list_extension_test.dart
index 3feb1c6a..9e472f7f 100644
--- a/app/test/list_extension_test.dart
+++ b/np_collection/test/list_extension_test.dart
@@ -1,4 +1,4 @@
-import 'package:nc_photos/list_extension.dart';
+import 'package:np_collection/src/list_extension.dart';
 import 'package:test/test.dart';
 
 void main() {
diff --git a/app/test/list_util_test.dart b/np_collection/test/list_util_test.dart
similarity index 80%
rename from app/test/list_util_test.dart
rename to np_collection/test/list_util_test.dart
index 3e46ed76..e8bd7c89 100644
--- a/app/test/list_util_test.dart
+++ b/np_collection/test/list_util_test.dart
@@ -1,4 +1,4 @@
-import 'package:nc_photos/list_util.dart' as list_util;
+import 'package:np_collection/src/list_util.dart';
 import 'package:test/test.dart';
 
 void main() {
@@ -26,7 +26,7 @@ void main() {
 /// b: [1, 2, 3, 4, 5]
 /// Expect: [1, 2], []
 void _diffExtraBBegin() {
-  final diff = list_util.diff([3, 4, 5], [1, 2, 3, 4, 5]);
+  final diff = getDiff([3, 4, 5], [1, 2, 3, 4, 5]);
   expect(diff.onlyInB, [1, 2]);
   expect(diff.onlyInA, []);
 }
@@ -37,7 +37,7 @@ void _diffExtraBBegin() {
 /// b: [1, 2, 3, 4, 5]
 /// Expect: [4, 5], []
 void _diffExtraBEnd() {
-  final diff = list_util.diff([1, 2, 3], [1, 2, 3, 4, 5]);
+  final diff = getDiff([1, 2, 3], [1, 2, 3, 4, 5]);
   expect(diff.onlyInB, [4, 5]);
   expect(diff.onlyInA, []);
 }
@@ -48,7 +48,7 @@ void _diffExtraBEnd() {
 /// b: [1, 2, 3, 4, 5]
 /// Expect: [3, 4], []
 void _diffExtraBMid() {
-  final diff = list_util.diff([1, 2, 5], [1, 2, 3, 4, 5]);
+  final diff = getDiff([1, 2, 5], [1, 2, 3, 4, 5]);
   expect(diff.onlyInB, [3, 4]);
   expect(diff.onlyInA, []);
 }
@@ -59,7 +59,7 @@ void _diffExtraBMid() {
 /// b: [1, 2, 3]
 /// Expect: [1, 2, 3], []
 void _diffAEmpty() {
-  final diff = list_util.diff(<int>[], [1, 2, 3]);
+  final diff = getDiff(<int>[], [1, 2, 3]);
   expect(diff.onlyInB, [1, 2, 3]);
   expect(diff.onlyInA, []);
 }
@@ -70,7 +70,7 @@ void _diffAEmpty() {
 /// b: [3, 4, 5]
 /// Expect: [], [1, 2]
 void _diffExtraABegin() {
-  final diff = list_util.diff([1, 2, 3, 4, 5], [3, 4, 5]);
+  final diff = getDiff([1, 2, 3, 4, 5], [3, 4, 5]);
   expect(diff.onlyInB, []);
   expect(diff.onlyInA, [1, 2]);
 }
@@ -81,7 +81,7 @@ void _diffExtraABegin() {
 /// b: [1, 2, 3]
 /// Expect: [], [4, 5]
 void _diffExtraAEnd() {
-  final diff = list_util.diff([1, 2, 3, 4, 5], [1, 2, 3]);
+  final diff = getDiff([1, 2, 3, 4, 5], [1, 2, 3]);
   expect(diff.onlyInB, []);
   expect(diff.onlyInA, [4, 5]);
 }
@@ -92,7 +92,7 @@ void _diffExtraAEnd() {
 /// b: [1, 2, 5]
 /// Expect: [], [3, 4]
 void _diffExtraAMid() {
-  final diff = list_util.diff([1, 2, 3, 4, 5], [1, 2, 5]);
+  final diff = getDiff([1, 2, 3, 4, 5], [1, 2, 5]);
   expect(diff.onlyInB, []);
   expect(diff.onlyInA, [3, 4]);
 }
@@ -103,7 +103,7 @@ void _diffExtraAMid() {
 /// b: []
 /// Expect: [], [1, 2, 3]
 void _diffBEmpty() {
-  final diff = list_util.diff([1, 2, 3], <int>[]);
+  final diff = getDiff([1, 2, 3], <int>[]);
   expect(diff.onlyInB, []);
   expect(diff.onlyInA, [1, 2, 3]);
 }
@@ -114,7 +114,7 @@ void _diffBEmpty() {
 /// b: [2, 4]
 /// Expect: [2, 4], [1, 3, 5]
 void _diffNoMatches() {
-  final diff = list_util.diff([1, 3, 5], [2, 4]);
+  final diff = getDiff([1, 3, 5], [2, 4]);
   expect(diff.onlyInB, [2, 4]);
   expect(diff.onlyInA, [1, 3, 5]);
 }
@@ -125,7 +125,7 @@ void _diffNoMatches() {
 /// b: [1, 2, 2, 3]
 /// Expect: [2], []
 void _diffRepeatedElements() {
-  final diff = list_util.diff([1, 2, 3], [1, 2, 2, 3]);
+  final diff = getDiff([1, 2, 3], [1, 2, 2, 3]);
   expect(diff.onlyInB, [2]);
   expect(diff.onlyInA, []);
 }
@@ -136,7 +136,7 @@ void _diffRepeatedElements() {
 /// b: [1, 2, 2, 3, 5]
 /// Expect: [2, 2], [4, 4]
 void _diffRepeatedElements2() {
-  final diff = list_util.diff([1, 3, 4, 4, 5], [1, 2, 2, 3, 5]);
+  final diff = getDiff([1, 3, 4, 4, 5], [1, 2, 2, 3, 5]);
   expect(diff.onlyInB, [2, 2]);
   expect(diff.onlyInA, [4, 4]);
 }
@@ -147,7 +147,7 @@ void _diffRepeatedElements2() {
 /// b: [1, 3, 4, 8, 13, 14]
 /// Expect: [1, 4, 8, 13, 14], [2, 7, 10, 11, 12]
 void _diffMix() {
-  final diff = list_util.diff([2, 3, 7, 10, 11, 12], [1, 3, 4, 8, 13, 14]);
+  final diff = getDiff([2, 3, 7, 10, 11, 12], [1, 3, 4, 8, 13, 14]);
   expect(diff.onlyInB, [1, 4, 8, 13, 14]);
   expect(diff.onlyInA, [2, 7, 10, 11, 12]);
 }