diff --git a/src/WeihanLi.Common/Event/EventBase.cs b/src/WeihanLi.Common/Event/EventBase.cs
index f76790a9..70e7a214 100644
--- a/src/WeihanLi.Common/Event/EventBase.cs
+++ b/src/WeihanLi.Common/Event/EventBase.cs
@@ -52,16 +52,22 @@ protected EventBase(string eventId, DateTimeOffset eventAt)
     }
 }
 
-internal interface IEventWrapper
+internal interface IEvent
 {
     EventProperties Properties { get; }
-    object Data { get; }
+    object? Data { get; }
 }
 
-internal sealed class EventWrapper<T> : IEventWrapper
+public interface IEvent<out T>
+{
+    EventProperties Properties { get; }
+    T Data { get; }
+}
+
+internal sealed class EventWrapper<T> : IEvent, IEvent<T>
 {
     public required T Data { get; init; }
-    object IEventWrapper.Data => Data!;
+    object? IEvent.Data => (object?)Data;
     public required EventProperties Properties { get; init; }
 }
 
diff --git a/src/WeihanLi.Common/Event/EventQueueInMemory.cs b/src/WeihanLi.Common/Event/EventQueueInMemory.cs
index c9d90a68..c6cb9122 100644
--- a/src/WeihanLi.Common/Event/EventQueueInMemory.cs
+++ b/src/WeihanLi.Common/Event/EventQueueInMemory.cs
@@ -9,7 +9,7 @@ namespace WeihanLi.Common.Event;
 
 public sealed class EventQueueInMemory : IEventQueue
 {
-    private readonly ConcurrentDictionary<string, ConcurrentQueue<IEventWrapper>> _eventQueues = new();
+    private readonly ConcurrentDictionary<string, ConcurrentQueue<IEvent>> _eventQueues = new();
 
     public ICollection<string> GetQueues() => _eventQueues.Keys;
 
@@ -35,7 +35,7 @@ public bool Enqueue<TEvent>(string queueName, TEvent @event, EventProperties? pr
             Data = @event,
             Properties = properties
         };
-        var queue = _eventQueues.GetOrAdd(queueName, _ => new ConcurrentQueue<IEventWrapper>());
+        var queue = _eventQueues.GetOrAdd(queueName, _ => new ConcurrentQueue<IEvent>());
         queue.Enqueue(internalEvent);
         return true;
     }
diff --git a/src/WeihanLi.Common/Event/EventStoreInMemory.cs b/src/WeihanLi.Common/Event/EventStoreInMemory.cs
index a453a2d9..e537bb5b 100644
--- a/src/WeihanLi.Common/Event/EventStoreInMemory.cs
+++ b/src/WeihanLi.Common/Event/EventStoreInMemory.cs
@@ -8,24 +8,19 @@ namespace WeihanLi.Common.Event;
 
 public sealed class EventStoreInMemory : IEventStore
 {
-    private readonly ConcurrentDictionary<string, IEventBase> _events = new();
+    private readonly ConcurrentDictionary<string, IEvent> _events = new();
 
-    public int SaveEvents(ICollection<IEventBase> events)
+    public Task<int> SaveEventsAsync(ICollection<IEvent> events)
     {
         if (events.IsNullOrEmpty())
-            return 0;
+            return Task.FromResult(0);
 
-        return events.Count(@event => _events.TryAdd(@event.EventId, @event));
+        return Task.FromResult(events.Count(@event => _events.TryAdd(@event.Properties.EventId, @event)));
     }
 
-    public Task<int> SaveEventsAsync(ICollection<IEventBase> events) => Task.FromResult(SaveEvents(events));
-
-    public int DeleteEvents(ICollection<string> eventIds)
+    private int DeleteEvents(ICollection<string> eventIds)
     {
-        if (eventIds.IsNullOrEmpty())
-            return 0;
-        
-        return eventIds.Count(eventId => _events.TryRemove(eventId, out _));
+        return eventIds.IsNullOrEmpty() ? 0 : eventIds.Count(eventId => _events.TryRemove(eventId, out _));
     }
 
     public Task<int> DeleteEventsAsync(ICollection<string> eventIds) => Task.FromResult(DeleteEvents(eventIds));
diff --git a/src/WeihanLi.Common/Event/IEventStore.cs b/src/WeihanLi.Common/Event/IEventStore.cs
index 65d5cb55..822b4080 100644
--- a/src/WeihanLi.Common/Event/IEventStore.cs
+++ b/src/WeihanLi.Common/Event/IEventStore.cs
@@ -5,8 +5,6 @@ namespace WeihanLi.Common.Event;
 
 public interface IEventStore
 {
-    int SaveEvents(ICollection<IEventBase> events);
-    Task<int> SaveEventsAsync(ICollection<IEventBase> events);
-    int DeleteEvents(ICollection<string> eventIds);
+    Task<int> SaveEventsAsync(ICollection<IEvent> events);
     Task<int> DeleteEventsAsync(ICollection<string> eventIds);
 }
diff --git a/src/WeihanLi.Common/Extensions/JsonSerializeExtension.cs b/src/WeihanLi.Common/Extensions/JsonSerializeExtension.cs
index 210a061e..8e8cafc3 100644
--- a/src/WeihanLi.Common/Extensions/JsonSerializeExtension.cs
+++ b/src/WeihanLi.Common/Extensions/JsonSerializeExtension.cs
@@ -21,7 +21,7 @@ public static class JsonSerializeExtension
 
     public static JsonSerializerSettings SerializerSettingsWith(Action<JsonSerializerSettings>? action)
     {
-        if (null == action)
+        if (action is null)
             return DefaultSerializerSettings;
 
         var serializerSettings = GetDefaultSerializerSettings();