diff --git a/backend/tests/Squidex.Infrastructure.Tests/EventSourcing/Consume/EventConsumerProcessorIntegrationTests.cs b/backend/tests/Squidex.Infrastructure.Tests/EventSourcing/Consume/EventConsumerProcessorIntegrationTests.cs
new file mode 100644
index 000000000..43a84acd5
--- /dev/null
+++ b/backend/tests/Squidex.Infrastructure.Tests/EventSourcing/Consume/EventConsumerProcessorIntegrationTests.cs
@@ -0,0 +1,142 @@
+// ==========================================================================
+//  Squidex Headless CMS
+// ==========================================================================
+//  Copyright (c) Squidex UG (haftungsbeschraenkt)
+//  All rights reserved. Licensed under the MIT license.
+// ==========================================================================
+
+using Microsoft.Extensions.DependencyInjection;
+using MongoDB.Driver;
+using Squidex.Caching;
+using Squidex.Infrastructure.Reflection;
+using Squidex.Infrastructure.States;
+using Squidex.Infrastructure.TestHelpers;
+using Xunit;
+
+namespace Squidex.Infrastructure.EventSourcing.Consume
+{
+    public abstract class EventConsumerProcessorIntegrationTests
+    {
+        private readonly Lazy<IEventStore> store;
+
+        public sealed class EventConsumer : IEventConsumer
+        {
+            public List<Guid> Events { get; } = new List<Guid>();
+
+            public string Name => "Consumer";
+
+            public Func<int, Task> EventReceived { get; set; }
+
+            public async Task On(Envelope<IEvent> @event)
+            {
+                Events.Add(@event.Headers.EventId());
+
+                if (EventReceived != null)
+                {
+                    await EventReceived(Events.Count);
+                }
+            }
+        }
+
+        protected IEventStore EventStore
+        {
+            get => store.Value;
+        }
+
+        protected EventConsumerProcessorIntegrationTests()
+        {
+#pragma warning disable MA0056 // Do not call overridable members in constructor
+            store = new Lazy<IEventStore>(CreateStore);
+#pragma warning restore MA0056 // Do not call overridable members in constructor
+        }
+
+        public abstract IEventStore CreateStore();
+
+        [Theory]
+        [InlineData(0)]
+        [InlineData(100)]
+        public async Task Should_subscribe_with_parallel_writes(int startStop)
+        {
+            var numTasks = 100;
+            var numEvents = 50;
+
+            var eventConsumer = new EventConsumer();
+
+            var mongoClient = new MongoClient(TestConfig.Configuration["mongodb:configuration"]);
+            var mongoDatabase = mongoClient.GetDatabase(TestConfig.Configuration["mongodb:database"]);
+
+            var typeFactory = new TypeNameRegistry().Map(typeof(MyEvent), "MyEvent");
+
+            var services = new ServiceCollection()
+                .AddLogging()
+                .AddSingleton(TestUtils.DefaultSerializer)
+                .AddSingleton(EventStore)
+                .AddSingleton(eventConsumer)
+                .AddSingleton(mongoClient)
+                .AddSingleton(mongoDatabase)
+                .AddSingleton(typeFactory)
+                .AddSingleton(typeof(IPersistenceFactory<>), typeof(Store<>))
+                .AddSingleton<EventConsumerProcessor>()
+                .AddSingleton<IEventConsumer>(eventConsumer)
+                .AddSingleton<IEventFormatter, DefaultEventFormatter>()
+                .AddSingleton<IEventStreamNames, DefaultEventStreamNames>()
+                .AddSingleton(typeof(ISnapshotStore<>), typeof(MongoSnapshotStore<>))
+                .BuildServiceProvider();
+
+            var processor = services.GetRequiredService<EventConsumerProcessor>();
+
+            var persistenceFactory = services.GetRequiredService<IPersistenceFactory<None>>();
+
+            // Also start the event consumer, because it might be stopped from previous run.
+            await processor.InitializeAsync(default);
+            await processor.ActivateAsync();
+            await processor.StartAsync();
+
+            async Task StartStop()
+            {
+                await processor.StopAsync();
+                await processor.StartAsync();
+            }
+
+            eventConsumer.EventReceived = i =>
+            {
+                if (startStop > 0 && i % startStop == 0)
+                {
+                    // Do not await the task here, other wise we could create deadlock.
+                    StartStop().Forget();
+                }
+
+                return Task.CompletedTask;
+            };
+
+            // Create events in parallel.
+            await Parallel.ForEachAsync(Enumerable.Range(0, numTasks), async (i, ct) =>
+            {
+                var persistence = persistenceFactory.WithEventSourcing(typeof(None), DomainId.NewGuid(), null);
+
+                for (var j = 0; j < numEvents; j++)
+                {
+                    await persistence.WriteEventsAsync(new List<Envelope<IEvent>>
+                    {
+                        Envelope.Create(new MyEvent())
+                    });
+                }
+            });
+
+            var expectedEvents = numEvents * numTasks;
+
+            // Wait for all events to arrive.
+            using (var cts = new CancellationTokenSource(20000))
+            {
+                while (!cts.IsCancellationRequested && eventConsumer.Events.Count < expectedEvents)
+                {
+                    await Task.Delay(100);
+                }
+            }
+
+            await processor.StopAsync();
+
+            Assert.Equal(expectedEvents, eventConsumer.Events.Count);
+        }
+    }
+}
diff --git a/backend/tests/Squidex.Infrastructure.Tests/EventSourcing/Consume/MongoEventConsumerProcessorIntegrationTests_Direct.cs b/backend/tests/Squidex.Infrastructure.Tests/EventSourcing/Consume/MongoEventConsumerProcessorIntegrationTests_Direct.cs
new file mode 100644
index 000000000..7aeccdef4
--- /dev/null
+++ b/backend/tests/Squidex.Infrastructure.Tests/EventSourcing/Consume/MongoEventConsumerProcessorIntegrationTests_Direct.cs
@@ -0,0 +1,29 @@
+// ==========================================================================
+//  Squidex Headless CMS
+// ==========================================================================
+//  Copyright (c) Squidex UG (haftungsbeschraenkt)
+//  All rights reserved. Licensed under the MIT license.
+// ==========================================================================
+
+using Xunit;
+
+#pragma warning disable SA1300 // Element should begin with upper-case letter
+
+namespace Squidex.Infrastructure.EventSourcing.Consume
+{
+    [Trait("Category", "Dependencies")]
+    public class MongoEventConsumerProcessorIntegrationTests_Direct : EventConsumerProcessorIntegrationTests, IClassFixture<MongoEventStoreDirectFixture>
+    {
+        public MongoEventStoreFixture _ { get; }
+
+        public MongoEventConsumerProcessorIntegrationTests_Direct(MongoEventStoreDirectFixture fixture)
+        {
+            _ = fixture;
+        }
+
+        public override IEventStore CreateStore()
+        {
+            return _.EventStore;
+        }
+    }
+}
diff --git a/backend/tests/Squidex.Infrastructure.Tests/EventSourcing/EventStoreTests.cs b/backend/tests/Squidex.Infrastructure.Tests/EventSourcing/EventStoreTests.cs
index 0dfb9b899..1c9f6abb6 100644
--- a/backend/tests/Squidex.Infrastructure.Tests/EventSourcing/EventStoreTests.cs
+++ b/backend/tests/Squidex.Infrastructure.Tests/EventSourcing/EventStoreTests.cs
@@ -232,14 +232,17 @@ namespace Squidex.Infrastructure.EventSourcing
         {
             var streamName = $"test-{Guid.NewGuid()}";
 
+            var numTasks = 50;
+            var numEvents = 100;
+
             // Append and read in parallel.
             var readEvents = await QueryWithSubscriptionAsync($"^{streamName}", async () =>
             {
-                await Parallel.ForEachAsync(Enumerable.Range(0, 50), async (i, ct) =>
+                await Parallel.ForEachAsync(Enumerable.Range(0, numTasks), async (i, ct) =>
                 {
                     var fullStreamName = $"{streamName}-{Guid.NewGuid()}";
 
-                    for (var j = 0; j < 100; j++)
+                    for (var j = 0; j < numEvents; j++)
                     {
                         var commit1 = new[]
                         {
@@ -251,7 +254,7 @@ namespace Squidex.Infrastructure.EventSourcing
                 });
             });
 
-            Assert.Equal(5000, readEvents?.Count);
+            Assert.Equal(numEvents * numTasks, readEvents?.Count);
         }
 
         [Fact]