diff --git a/src/Squidex.Domain.Apps.Entities/Assets/BackupAssets.cs b/src/Squidex.Domain.Apps.Entities/Assets/BackupAssets.cs
index e49efeb4d..e9157981f 100644
--- a/src/Squidex.Domain.Apps.Entities/Assets/BackupAssets.cs
+++ b/src/Squidex.Domain.Apps.Entities/Assets/BackupAssets.cs
@@ -7,7 +7,9 @@
 
 using System;
 using System.Collections.Generic;
+using System.IO;
 using System.Threading.Tasks;
+using Newtonsoft.Json;
 using Squidex.Domain.Apps.Entities.Assets.Repositories;
 using Squidex.Domain.Apps.Entities.Assets.State;
 using Squidex.Domain.Apps.Entities.Backup;
@@ -23,6 +25,7 @@ namespace Squidex.Domain.Apps.Entities.Assets
 {
     public sealed class BackupAssets : BackupHandlerWithStore
     {
+        private static readonly JsonSerializer Serializer = JsonSerializer.Create();
         private readonly HashSet<Guid> assetIds = new HashSet<Guid>();
         private readonly IAssetStore assetStore;
         private readonly IAssetRepository assetRepository;
@@ -73,6 +76,11 @@ namespace Squidex.Domain.Apps.Entities.Assets
             return TaskHelper.Done;
         }
 
+        public override Task BackupAsync(Guid appId, BackupWriter writer)
+        {
+            return BackupTagsAsync(appId, writer);
+        }
+
         public override Task RestoreEventAsync(Envelope<IEvent> @event, Guid appId, BackupReader reader)
         {
             switch (@event.Payload)
@@ -88,9 +96,37 @@ namespace Squidex.Domain.Apps.Entities.Assets
             return TaskHelper.Done;
         }
 
-        public override Task RestoreAsync(Guid appId, BackupReader reader)
+        public override async Task RestoreAsync(Guid appId, BackupReader reader)
+        {
+            await RestoreTagsAsync(appId, reader);
+
+            await RebuildManyAsync(assetIds, id => RebuildAsync<AssetState, AssetGrain>(id, (e, s) => s.Apply(e)));
+        }
+
+        private Task RestoreTagsAsync(Guid appId, BackupReader reader)
+        {
+            return reader.ReadAttachmentAsync("AssetTags.json", async stream =>
+            {
+                using (var textReader = new StreamReader(stream))
+                {
+                    var tags = (TagSet)Serializer.Deserialize(textReader, typeof(TagSet));
+
+                    await tagService.RebuildTagsAsync(appId, TagGroups.Assets, tags);
+                }
+            });
+        }
+
+        private Task BackupTagsAsync(Guid appId, BackupWriter writer)
         {
-            return RebuildManyAsync(assetIds, id => RebuildAsync<AssetState, AssetGrain>(id, (e, s) => s.Apply(e)));
+            return writer.WriteAttachmentAsync("AssetTags.json", async stream =>
+            {
+                var tags = await tagService.GetExportableTagsAsync(appId, TagGroups.Assets);
+
+                using (var textWriter = new StreamWriter(stream))
+                {
+                    Serializer.Serialize(textWriter, tags);
+                }
+            });
         }
 
         private Task WriteAssetAsync(Guid assetId, long fileVersion, BackupWriter writer)
diff --git a/src/Squidex.Domain.Apps.Entities/Backup/IBackupGrain.cs b/src/Squidex.Domain.Apps.Entities/Backup/IBackupGrain.cs
index ec545f3dd..aa48fdbd4 100644
--- a/src/Squidex.Domain.Apps.Entities/Backup/IBackupGrain.cs
+++ b/src/Squidex.Domain.Apps.Entities/Backup/IBackupGrain.cs
@@ -8,16 +8,19 @@
 using System;
 using System.Collections.Generic;
 using System.Threading.Tasks;
+using Orleans;
 using Squidex.Infrastructure.Orleans;
 
 namespace Squidex.Domain.Apps.Entities.Backup
 {
-    public interface IBackupGrain : ICleanableAppGrain
+    public interface IBackupGrain : IGrainWithGuidKey
     {
         Task RunAsync();
 
         Task DeleteAsync(Guid id);
 
+        Task ClearAsync();
+
         Task<J<List<IBackupJob>>> GetStateAsync();
     }
 }
diff --git a/src/Squidex.Domain.Apps.Entities/Rules/Indexes/IRulesByAppIndex.cs b/src/Squidex.Domain.Apps.Entities/Rules/Indexes/IRulesByAppIndex.cs
index e1e7ac82c..a58689e4c 100644
--- a/src/Squidex.Domain.Apps.Entities/Rules/Indexes/IRulesByAppIndex.cs
+++ b/src/Squidex.Domain.Apps.Entities/Rules/Indexes/IRulesByAppIndex.cs
@@ -8,10 +8,11 @@
 using System;
 using System.Collections.Generic;
 using System.Threading.Tasks;
+using Orleans;
 
 namespace Squidex.Domain.Apps.Entities.Rules.Indexes
 {
-    public interface IRulesByAppIndex : ICleanableAppGrain
+    public interface IRulesByAppIndex : IGrainWithGuidKey
     {
         Task AddRuleAsync(Guid ruleId);
 
@@ -19,6 +20,8 @@ namespace Squidex.Domain.Apps.Entities.Rules.Indexes
 
         Task RebuildAsync(HashSet<Guid> rules);
 
+        Task ClearAsync();
+
         Task<List<Guid>> GetRuleIdsAsync();
     }
 }
diff --git a/src/Squidex.Domain.Apps.Entities/Schemas/Indexes/ISchemasByAppIndex.cs b/src/Squidex.Domain.Apps.Entities/Schemas/Indexes/ISchemasByAppIndex.cs
index 701caa5ad..0cffd11a9 100644
--- a/src/Squidex.Domain.Apps.Entities/Schemas/Indexes/ISchemasByAppIndex.cs
+++ b/src/Squidex.Domain.Apps.Entities/Schemas/Indexes/ISchemasByAppIndex.cs
@@ -8,10 +8,11 @@
 using System;
 using System.Collections.Generic;
 using System.Threading.Tasks;
+using Orleans;
 
 namespace Squidex.Domain.Apps.Entities.Schemas.Indexes
 {
-    public interface ISchemasByAppIndex : ICleanableAppGrain
+    public interface ISchemasByAppIndex : IGrainWithGuidKey
     {
         Task AddSchemaAsync(Guid schemaId, string name);
 
@@ -19,6 +20,8 @@ namespace Squidex.Domain.Apps.Entities.Schemas.Indexes
 
         Task RebuildAsync(Dictionary<string, Guid> schemas);
 
+        Task ClearAsync();
+
         Task<Guid> GetSchemaIdAsync(string name);
 
         Task<List<Guid>> GetSchemaIdsAsync();
diff --git a/src/Squidex.Domain.Apps.Entities/Tags/GrainTagService.cs b/src/Squidex.Domain.Apps.Entities/Tags/GrainTagService.cs
index 48d7e1e49..d88dd023a 100644
--- a/src/Squidex.Domain.Apps.Entities/Tags/GrainTagService.cs
+++ b/src/Squidex.Domain.Apps.Entities/Tags/GrainTagService.cs
@@ -49,9 +49,14 @@ namespace Squidex.Domain.Apps.Entities.Tags
             return GetGrain(appId, group).GetTagsAsync();
         }
 
-        public Task RebuildTagsAsync(Guid appId, string group, Dictionary<string, string> allTags)
+        public Task<TagSet> GetExportableTagsAsync(Guid appId, string group)
         {
-            return GetGrain(appId, group).RebuildTagsAsync(allTags);
+            return GetGrain(appId, group).GetExportableTagsAsync();
+        }
+
+        public Task RebuildTagsAsync(Guid appId, string group, TagSet tags)
+        {
+            return GetGrain(appId, group).RebuildAsync(tags);
         }
 
         public Task ClearAsync(Guid appId, string group)
diff --git a/src/Squidex.Domain.Apps.Entities/Tags/ITagGrain.cs b/src/Squidex.Domain.Apps.Entities/Tags/ITagGrain.cs
index 8218255c8..952702b10 100644
--- a/src/Squidex.Domain.Apps.Entities/Tags/ITagGrain.cs
+++ b/src/Squidex.Domain.Apps.Entities/Tags/ITagGrain.cs
@@ -21,7 +21,10 @@ namespace Squidex.Domain.Apps.Entities.Tags
 
         Task<Dictionary<string, int>> GetTagsAsync();
 
+        Task<TagSet> GetExportableTagsAsync();
+
         Task ClearAsync();
-        Task RebuildTagsAsync(Dictionary<string, string> allTags);
+
+        Task RebuildAsync(TagSet tags);
     }
 }
diff --git a/src/Squidex.Domain.Apps.Entities/Tags/ITagService.cs b/src/Squidex.Domain.Apps.Entities/Tags/ITagService.cs
index 19724eb1b..01fb3c9e8 100644
--- a/src/Squidex.Domain.Apps.Entities/Tags/ITagService.cs
+++ b/src/Squidex.Domain.Apps.Entities/Tags/ITagService.cs
@@ -21,7 +21,9 @@ namespace Squidex.Domain.Apps.Entities.Tags
 
         Task<Dictionary<string, int>> GetTagsAsync(Guid appId, string group);
 
-        Task RebuildTagsAsync(Guid appId, string group, Dictionary<string, string> allTags);
+        Task<TagSet> GetExportableTagsAsync(Guid appId, string group);
+
+        Task RebuildTagsAsync(Guid appId, string group, TagSet tags);
 
         Task ClearAsync(Guid appId, string group);
     }
diff --git a/src/Squidex.Domain.Apps.Entities/Tags/Tag.cs b/src/Squidex.Domain.Apps.Entities/Tags/Tag.cs
new file mode 100644
index 000000000..60fab8187
--- /dev/null
+++ b/src/Squidex.Domain.Apps.Entities/Tags/Tag.cs
@@ -0,0 +1,16 @@
+// ==========================================================================
+//  Squidex Headless CMS
+// ==========================================================================
+//  Copyright (c) Squidex UG (haftungsbeschraenkt)
+//  All rights reserved. Licensed under the MIT license.
+// ==========================================================================
+
+namespace Squidex.Domain.Apps.Entities.Tags
+{
+    public sealed class Tag
+    {
+        public string Name { get; set; }
+
+        public int Count { get; set; } = 1;
+    }
+}
diff --git a/src/Squidex.Domain.Apps.Entities/Tags/TagGrain.cs b/src/Squidex.Domain.Apps.Entities/Tags/TagGrain.cs
index a40110ac4..f4d837206 100644
--- a/src/Squidex.Domain.Apps.Entities/Tags/TagGrain.cs
+++ b/src/Squidex.Domain.Apps.Entities/Tags/TagGrain.cs
@@ -24,14 +24,7 @@ namespace Squidex.Domain.Apps.Entities.Tags
         [CollectionName("Index_Tags")]
         public sealed class State
         {
-            public Dictionary<string, TagInfo> Tags { get; set; } = new Dictionary<string, TagInfo>();
-        }
-
-        public sealed class TagInfo
-        {
-            public string Name { get; set; }
-
-            public int Count { get; set; } = 1;
+            public TagSet Tags { get; set; } = new TagSet();
         }
 
         public TagGrain(IStore<string> store)
@@ -58,9 +51,11 @@ namespace Squidex.Domain.Apps.Entities.Tags
             return persistence.DeleteAsync();
         }
 
-        public Task RebuildTagsAsync(Dictionary<string, string> allTags)
+        public Task RebuildAsync(TagSet tags)
         {
-            throw new NotImplementedException();
+            state.Tags = tags;
+
+            return persistence.DeleteAsync();
         }
 
         public async Task<HashSet<string>> NormalizeTagsAsync(HashSet<string> names, HashSet<string> ids)
@@ -91,7 +86,7 @@ namespace Squidex.Domain.Apps.Entities.Tags
                         {
                             tagId = Guid.NewGuid().ToString();
 
-                            state.Tags.Add(tagId, new TagInfo { Name = tagName });
+                            state.Tags.Add(tagId, new Tag { Name = tagName });
                         }
 
                         result.Add(tagId);
@@ -159,5 +154,10 @@ namespace Squidex.Domain.Apps.Entities.Tags
         {
             return Task.FromResult(state.Tags.Values.ToDictionary(x => x.Name, x => x.Count));
         }
+
+        public Task<TagSet> GetExportableTagsAsync()
+        {
+            return Task.FromResult(state.Tags);
+        }
     }
 }
diff --git a/src/Squidex.Domain.Apps.Entities/Tags/TagSet.cs b/src/Squidex.Domain.Apps.Entities/Tags/TagSet.cs
new file mode 100644
index 000000000..48815870e
--- /dev/null
+++ b/src/Squidex.Domain.Apps.Entities/Tags/TagSet.cs
@@ -0,0 +1,15 @@
+// ==========================================================================
+//  Squidex Headless CMS
+// ==========================================================================
+//  Copyright (c) Squidex UG (haftungsbeschraenkt)
+//  All rights reserved. Licensed under the MIT license.
+// ==========================================================================
+
+using System.Collections.Generic;
+
+namespace Squidex.Domain.Apps.Entities.Tags
+{
+    public sealed class TagSet : Dictionary<string, Tag>
+    {
+    }
+}
diff --git a/src/Squidex/Config/Domain/EntitiesServices.cs b/src/Squidex/Config/Domain/EntitiesServices.cs
index 9f704a490..b690a4d1b 100644
--- a/src/Squidex/Config/Domain/EntitiesServices.cs
+++ b/src/Squidex/Config/Domain/EntitiesServices.cs
@@ -96,7 +96,8 @@ namespace Squidex.Config.Domain
             services.AddSingletonAs<JintScriptEngine>()
                 .As<IScriptEngine>();
 
-            AddCommandPipeline(services);
+            services.AddCommandPipeline();
+            services.AddBackupHandlers();
 
             services.AddSingleton<Func<IGrainCallContext, string>>(DomainObjectGrainFormatter.Format);
 
@@ -119,7 +120,7 @@ namespace Squidex.Config.Domain
             });
         }
 
-        private static void AddCommandPipeline(IServiceCollection services)
+        private static void AddCommandPipeline(this IServiceCollection services)
         {
             services.AddSingletonAs<InMemoryCommandBus>()
                 .As<ICommandBus>();
@@ -145,6 +146,9 @@ namespace Squidex.Config.Domain
             services.AddSingletonAs<AssetCommandMiddleware>()
                 .As<ICommandMiddleware>();
 
+            services.AddSingletonAs<AppsByNameIndexCommandMiddleware>()
+                .As<ICommandMiddleware>();
+
             services.AddSingletonAs<GrainCommandMiddleware<AppCommand, IAppGrain>>()
                 .As<ICommandMiddleware>();
 
@@ -157,9 +161,6 @@ namespace Squidex.Config.Domain
             services.AddSingletonAs<GrainCommandMiddleware<RuleCommand, IRuleGrain>>()
                 .As<ICommandMiddleware>();
 
-            services.AddSingletonAs<AppsByNameIndexCommandMiddleware>()
-                .As<ICommandMiddleware>();
-
             services.AddSingletonAs<AppsByUserIndexCommandMiddleware>()
                 .As<ICommandMiddleware>();
 
@@ -182,6 +183,16 @@ namespace Squidex.Config.Domain
                 .As<ICommandMiddleware>();
         }
 
+        private static void AddBackupHandlers(this IServiceCollection services)
+        {
+            services.AddTransient<BackupApps>();
+            services.AddTransient<BackupAssets>();
+            services.AddTransient<BackupContents>();
+            services.AddTransient<BackupHistory>();
+            services.AddTransient<BackupRules>();
+            services.AddTransient<BackupSchemas>();
+        }
+
         public static void AddMyMigrationServices(this IServiceCollection services)
         {
             services.AddSingletonAs<Migrator>()
diff --git a/tests/Squidex.Domain.Apps.Entities.Tests/Apps/Indexes/AppsByNameIndexGrainTests.cs b/tests/Squidex.Domain.Apps.Entities.Tests/Apps/Indexes/AppsByNameIndexGrainTests.cs
index 7667f15a8..368b9c417 100644
--- a/tests/Squidex.Domain.Apps.Entities.Tests/Apps/Indexes/AppsByNameIndexGrainTests.cs
+++ b/tests/Squidex.Domain.Apps.Entities.Tests/Apps/Indexes/AppsByNameIndexGrainTests.cs
@@ -47,6 +47,64 @@ namespace Squidex.Domain.Apps.Entities.Apps.Indexes
                 .MustHaveHappened();
         }
 
+        [Fact]
+        public async Task Should_not_be_able_to_reserve_index_if_name_taken()
+        {
+            await sut.AddAppAsync(appId2, appName1);
+
+            Assert.False(await sut.ReserveAppAsync(appId1, appName1));
+        }
+
+        [Fact]
+        public async Task Should_not_be_able_to_reserve_if_name_reserved()
+        {
+            await sut.ReserveAppAsync(appId2, appName1);
+
+            Assert.False(await sut.ReserveAppAsync(appId1, appName1));
+        }
+
+        [Fact]
+        public async Task Should_not_be_able_to_reserve_if_id_taken()
+        {
+            await sut.AddAppAsync(appId1, appName1);
+
+            Assert.False(await sut.ReserveAppAsync(appId1, appName2));
+        }
+
+        [Fact]
+        public async Task Should_not_be_able_to_reserve_if_id_reserved()
+        {
+            await sut.ReserveAppAsync(appId1, appName1);
+
+            Assert.False(await sut.ReserveAppAsync(appId1, appName2));
+        }
+
+        [Fact]
+        public async Task Should_be_able_to_reserve_if_id_and_name_not_reserved()
+        {
+            await sut.ReserveAppAsync(appId1, appName1);
+
+            Assert.True(await sut.ReserveAppAsync(appId2, appName2));
+        }
+
+        [Fact]
+        public async Task Should_be_able_to_reserve_after_app_removed()
+        {
+            await sut.AddAppAsync(appId1, appName1);
+            await sut.RemoveAppAsync(appId1);
+
+            Assert.True(await sut.ReserveAppAsync(appId1, appName1));
+        }
+
+        [Fact]
+        public async Task Should_be_able_to_reserve_after_reservation_removed()
+        {
+            await sut.ReserveAppAsync(appId1, appName1);
+            await sut.RemoveReservationAsync(appId1, appName1);
+
+            Assert.True(await sut.ReserveAppAsync(appId1, appName1));
+        }
+
         [Fact]
         public async Task Should_remove_app_id_from_index()
         {
diff --git a/tests/Squidex.Domain.Apps.Entities.Tests/Tags/GrainTagServiceTests.cs b/tests/Squidex.Domain.Apps.Entities.Tests/Tags/GrainTagServiceTests.cs
index 563429da0..c3667ee77 100644
--- a/tests/Squidex.Domain.Apps.Entities.Tests/Tags/GrainTagServiceTests.cs
+++ b/tests/Squidex.Domain.Apps.Entities.Tests/Tags/GrainTagServiceTests.cs
@@ -44,6 +44,26 @@ namespace Squidex.Domain.Apps.Entities.Tags
                 .MustHaveHappened();
         }
 
+        [Fact]
+        public async Task Should_call_grain_when_rebuilding()
+        {
+            var tags = new TagSet();
+
+            await sut.RebuildTagsAsync(appId, TagGroups.Assets, tags);
+
+            A.CallTo(() => grain.RebuildAsync(tags))
+                .MustHaveHappened();
+        }
+
+        [Fact]
+        public async Task Should_call_grain_when_retrieving_raw_tags()
+        {
+            await sut.GetExportableTagsAsync(appId, TagGroups.Assets);
+
+            A.CallTo(() => grain.GetTagsAsync())
+                .MustHaveHappened();
+        }
+
         [Fact]
         public async Task Should_call_grain_when_retrieving_tags()
         {
diff --git a/tests/Squidex.Domain.Apps.Entities.Tests/Tags/TagGrainTests.cs b/tests/Squidex.Domain.Apps.Entities.Tests/Tags/TagGrainTests.cs
index 998252ada..90b9fa0c8 100644
--- a/tests/Squidex.Domain.Apps.Entities.Tests/Tags/TagGrainTests.cs
+++ b/tests/Squidex.Domain.Apps.Entities.Tests/Tags/TagGrainTests.cs
@@ -45,6 +45,30 @@ namespace Squidex.Domain.Apps.Entities.Tags
                 .MustHaveHappened();
         }
 
+        [Fact]
+        public async Task Should_rebuild_tags()
+        {
+            var tags = new TagSet
+            {
+                ["1"] = new Tag { Name = "tag1", Count = 1 },
+                ["2"] = new Tag { Name = "tag2", Count = 2 },
+                ["3"] = new Tag { Name = "tag3", Count = 6 }
+            };
+
+            await sut.RebuildAsync(tags);
+
+            var allTags = await sut.GetTagsAsync();
+
+            Assert.Equal(new Dictionary<string, int>
+            {
+                ["tag1"] = 1,
+                ["tag2"] = 2,
+                ["tag3"] = 6
+            }, allTags);
+
+            Assert.Same(tags, await sut.GetExportableTagsAsync());
+        }
+
         [Fact]
         public async Task Should_add_tags_to_grain()
         {
diff --git a/tools/Migrate_01/Migrations/AddPatterns.cs b/tools/Migrate_01/Migrations/AddPatterns.cs
index 693435f22..4426982c6 100644
--- a/tools/Migrate_01/Migrations/AddPatterns.cs
+++ b/tools/Migrate_01/Migrations/AddPatterns.cs
@@ -10,6 +10,7 @@ using System.Threading.Tasks;
 using Orleans;
 using Squidex.Domain.Apps.Entities.Apps;
 using Squidex.Domain.Apps.Entities.Apps.Commands;
+using Squidex.Domain.Apps.Entities.Apps.Indexes;
 using Squidex.Infrastructure.Migrations;
 using Squidex.Infrastructure.Orleans;
 
diff --git a/tools/Migrate_01/Migrations/PopulateGrainIndexes.cs b/tools/Migrate_01/Migrations/PopulateGrainIndexes.cs
index 225e67a10..24ed5e092 100644
--- a/tools/Migrate_01/Migrations/PopulateGrainIndexes.cs
+++ b/tools/Migrate_01/Migrations/PopulateGrainIndexes.cs
@@ -9,8 +9,11 @@ using System;
 using System.Collections.Generic;
 using System.Threading.Tasks;
 using Orleans;
+using Squidex.Domain.Apps.Entities.Apps.Indexes;
 using Squidex.Domain.Apps.Entities.Apps.State;
+using Squidex.Domain.Apps.Entities.Rules.Indexes;
 using Squidex.Domain.Apps.Entities.Rules.State;
+using Squidex.Domain.Apps.Entities.Schemas.Indexes;
 using Squidex.Domain.Apps.Entities.Schemas.State;
 using Squidex.Infrastructure;
 using Squidex.Infrastructure.Migrations;