diff --git a/database/lib/src/database.dart b/database/lib/src/database.dart
index fcb7af7..0a912bd 100644
--- a/database/lib/src/database.dart
+++ b/database/lib/src/database.dart
@@ -7,26 +7,68 @@ part 'database.g.dart';
 final _random = Random(DateTime.now().millisecondsSinceEpoch);
 int generateId() => _random.nextInt(0xFFFFFFFF);
 
-class WorkModel {
+class WorkPartData {
   final Work work;
   final List<int> instrumentIds;
 
-  WorkModel({
-    @required this.work,
-    @required this.instrumentIds,
+  WorkPartData({
+    this.work,
+    this.instrumentIds,
   });
+
+  factory WorkPartData.fromJson(Map<String, dynamic> json) => WorkPartData(
+        work: Work.fromJson(json['work']),
+        instrumentIds: List<int>.from(json['instrumentIds']),
+      );
+
+  Map<String, dynamic> toJson() => {
+        'work': work.toJson(),
+        'instrumentIds': instrumentIds,
+      };
 }
 
-class PerformanceModel {
-  final Person person;
-  final Ensemble ensemble;
-  final Instrument role;
+class WorkData {
+  final WorkPartData data;
+  final List<WorkPartData> partData;
 
-  PerformanceModel({
-    this.person,
-    this.ensemble,
-    this.role,
+  WorkData({
+    this.data,
+    this.partData,
   });
+
+  factory WorkData.fromJson(Map<String, dynamic> json) => WorkData(
+        data: WorkPartData.fromJson(json['data']),
+        partData: json['partData']
+            .map<WorkPartData>((j) => WorkPartData.fromJson(j))
+            .toList(),
+      );
+
+  Map<String, dynamic> toJson() => {
+        'data': data.toJson(),
+        'partData': partData.map((d) => d.toJson()).toList(),
+      };
+}
+
+class RecordingData {
+  final Recording recording;
+  final List<Performance> performances;
+
+  RecordingData({
+    this.recording,
+    this.performances,
+  });
+
+  factory RecordingData.fromJson(Map<String, dynamic> json) => RecordingData(
+        recording: Recording.fromJson(json['recording']),
+        performances: json['performances']
+            .map<Performance>((j) => Performance.fromJson(j))
+            .toList(),
+      );
+
+  Map<String, dynamic> toJson() => {
+        'recording': recording.toJson(),
+        'performances': performances.map((p) => p.toJson()).toList(),
+      };
 }
 
 @UseMoor(
@@ -57,25 +99,25 @@ class Database extends _$Database {
     await into(instruments).insert(instrument, orReplace: true);
   }
 
-  Future<void> updateWork(WorkModel model, List<WorkModel> parts) async {
+  Future<void> updateWork(WorkData data) async {
     await transaction(() async {
-      final workId = model.work.id;
+      final workId = data.data.work.id;
       await (delete(works)..where((w) => w.id.equals(workId))).go();
       await (delete(works)..where((w) => w.partOf.equals(workId))).go();
 
-      Future<void> insertWork(WorkModel model) async {
-        await into(works).insert(model.work);
+      Future<void> insertWork(WorkPartData partData) async {
+        await into(works).insert(partData.work);
         await batch((b) => b.insertAll(
             instrumentations,
-            model.instrumentIds
+            partData.instrumentIds
                 .map((id) =>
-                    Instrumentation(work: model.work.id, instrument: id))
+                    Instrumentation(work: partData.work.id, instrument: id))
                 .toList()));
       }
 
-      await insertWork(model);
-      for (final part in parts) {
-        await insertWork(part);
+      await insertWork(data.data);
+      for (final partData in data.partData) {
+        await insertWork(partData);
       }
     });
   }
@@ -84,20 +126,14 @@ class Database extends _$Database {
     await into(ensembles).insert(ensemble, orReplace: true);
   }
 
-  Future<void> updateRecording(
-      Recording recording, List<PerformanceModel> models) async {
+  Future<void> updateRecording(RecordingData data) async {
     await transaction(() async {
       await (delete(performances)
-            ..where((p) => p.recording.equals(recording.id)))
+            ..where((p) => p.recording.equals(data.recording.id)))
           .go();
-      await into(recordings).insert(recording, orReplace: true);
-      for (final model in models) {
-        await into(performances).insert(Performance(
-          recording: recording.id,
-          person: model.person?.id,
-          ensemble: model.ensemble?.id,
-          role: model.role?.id,
-        ));
+      await into(recordings).insert(data.recording, orReplace: true);
+      for (final performance in data.performances) {
+        await into(performances).insert(performance);
       }
     });
   }
diff --git a/mobile/lib/editors/recording.dart b/mobile/lib/editors/recording.dart
index 9d2beb7..4934cf5 100644
--- a/mobile/lib/editors/recording.dart
+++ b/mobile/lib/editors/recording.dart
@@ -21,7 +21,7 @@ class _RecordingEditorState extends State<RecordingEditor> {
   final commentController = TextEditingController();
 
   Work work;
-  List<PerformanceModel> performances = [];
+  List<PerformanceModel> performanceModels = [];
 
   @override
   void initState() {
@@ -64,7 +64,20 @@ class _RecordingEditorState extends State<RecordingEditor> {
                 comment: commentController.text,
               );
 
-              await backend.db.updateRecording(recording, performances);
+              final performances = performanceModels
+                  .map((m) => Performance(
+                        recording: recording.id,
+                        person: m.person?.id,
+                        ensemble: m.ensemble?.id,
+                        role: m.role?.id,
+                      ))
+                  .toList();
+
+              await backend.db.updateRecording(RecordingData(
+                recording: recording,
+                performances: performances,
+              ));
+
               Navigator.pop(context, recording);
             },
           )
@@ -74,10 +87,10 @@ class _RecordingEditorState extends State<RecordingEditor> {
         children: <Widget>[
           work != null
               ? ListTile(
-                title: WorkText(work.id),
-                subtitle: ComposersText(work.id),
-                onTap: selectWork,
-              )
+                  title: WorkText(work.id),
+                  subtitle: ComposersText(work.id),
+                  onTap: selectWork,
+                )
               : ListTile(
                   title: Text('Work'),
                   subtitle: Text('Select work'),
@@ -111,13 +124,13 @@ class _RecordingEditorState extends State<RecordingEditor> {
 
                 if (model != null) {
                   setState(() {
-                    performances.add(model);
+                    performanceModels.add(model);
                   });
                 }
               },
             ),
           ),
-          for (final performance in performances)
+          for (final performance in performanceModels)
             ListTile(
               title: Text(performance.person != null
                   ? '${performance.person.firstName} ${performance.person.lastName}'
@@ -128,7 +141,7 @@ class _RecordingEditorState extends State<RecordingEditor> {
                 icon: const Icon(Icons.delete),
                 onPressed: () {
                   setState(() {
-                    performances.remove(performance);
+                    performanceModels.remove(performance);
                   });
                 },
               ),
diff --git a/mobile/lib/editors/work.dart b/mobile/lib/editors/work.dart
index 145acc7..f1b0adf 100644
--- a/mobile/lib/editors/work.dart
+++ b/mobile/lib/editors/work.dart
@@ -295,7 +295,7 @@ class _WorkEditorState extends State<WorkEditor> {
             onPressed: () async {
               final workId = widget.work?.id ?? generateId();
 
-              final model = WorkModel(
+              final data = WorkPartData(
                 work: Work(
                   id: workId,
                   title: titleController.text,
@@ -304,10 +304,10 @@ class _WorkEditorState extends State<WorkEditor> {
                 instrumentIds: instruments.map((i) => i.id).toList(),
               );
 
-              final List<WorkModel> partModels = [];
+              final List<WorkPartData> partData = [];
               for (var i = 0; i < parts.length; i++) {
                 final part = parts[i];
-                partModels.add(WorkModel(
+                partData.add(WorkPartData(
                   work: Work(
                     id: generateId(),
                     title: part.titleController.text,
@@ -319,8 +319,12 @@ class _WorkEditorState extends State<WorkEditor> {
                 ));
               }
 
-              await backend.db.updateWork(model, partModels);
-              Navigator.pop(context, model.work);
+              await backend.db.updateWork(WorkData(
+                data: data,
+                partData: partData,
+              ));
+
+              Navigator.pop(context, data.work);
             },
           ),
         ],
diff --git a/mobile/lib/selectors/performer.dart b/mobile/lib/selectors/performer.dart
index b270c27..dcc66a0 100644
--- a/mobile/lib/selectors/performer.dart
+++ b/mobile/lib/selectors/performer.dart
@@ -7,6 +7,18 @@ import '../editors/person.dart';
 
 import 'instruments.dart';
 
+class PerformanceModel {
+  final Person person;
+  final Ensemble ensemble;
+  final Instrument role;
+
+  PerformanceModel({
+    this.person,
+    this.ensemble,
+    this.role,
+  });
+}
+
 class PerformerSelector extends StatefulWidget {
   @override
   _PerformerSelectorState createState() => _PerformerSelectorState();