diff --git a/src/JKang.EventSourcing.Abstractions/Domain/Aggregate.cs b/src/JKang.EventSourcing.Abstractions/Domain/Aggregate.cs
index cec5555..7ead5f1 100644
--- a/src/JKang.EventSourcing.Abstractions/Domain/Aggregate.cs
+++ b/src/JKang.EventSourcing.Abstractions/Domain/Aggregate.cs
@@ -161,6 +161,7 @@ private void IntegrateSnapshot(IAggregateSnapshot<TKey> snapshot)
         internal class Changeset : IAggregateChangeset<TKey>
         {
             private readonly Aggregate<TKey> _aggregate;
+            private bool _committed = false;
 
             public Changeset(
                 Aggregate<TKey> aggregate,
@@ -182,6 +183,11 @@ public Changeset(
 
             public void Commit()
             {
+                if (_committed)
+                {
+                    throw new InvalidOperationException("The changeset is already committed");
+                }
+
                 for (int i = 0; i < Events.Count(); i++)
                 {
                     IAggregateEvent<TKey> @evt = _aggregate._unsavedEvents.Dequeue();
@@ -189,6 +195,7 @@ public void Commit()
                 }
 
                 _aggregate._unsavedSnapshot = null;
+                _committed = true;
             }
         }
     }
diff --git a/src/JKang.EventSourcing.Abstractions/Domain/IAggregateChangeset.cs b/src/JKang.EventSourcing.Abstractions/Domain/IAggregateChangeset.cs
index 98c4580..dca8a63 100644
--- a/src/JKang.EventSourcing.Abstractions/Domain/IAggregateChangeset.cs
+++ b/src/JKang.EventSourcing.Abstractions/Domain/IAggregateChangeset.cs
@@ -1,5 +1,4 @@
 using JKang.EventSourcing.Events;
-using JKang.EventSourcing.Snapshotting;
 using System.Collections.Generic;
 
 namespace JKang.EventSourcing.Domain
diff --git a/src/JKang.EventSourcing.Abstractions/Persistence/AggregateRepository.cs b/src/JKang.EventSourcing.Abstractions/Persistence/AggregateRepository.cs
index 9433bca..12d171f 100644
--- a/src/JKang.EventSourcing.Abstractions/Persistence/AggregateRepository.cs
+++ b/src/JKang.EventSourcing.Abstractions/Persistence/AggregateRepository.cs
@@ -22,7 +22,7 @@ protected AggregateRepository(
             _snapshotStore = snapshotStore ?? throw new ArgumentNullException(nameof(snapshotStore));
         }
 
-        protected async Task SaveAggregateAsync(TAggregate aggregate,
+        protected async Task<IAggregateChangeset<TKey>> SaveAggregateAsync(TAggregate aggregate,
             CancellationToken cancellationToken = default)
         {
             if (aggregate is null)
@@ -35,24 +35,17 @@ protected async Task SaveAggregateAsync(TAggregate aggregate,
             foreach (IAggregateEvent<TKey> @event in changeset.Events)
             {
                 await _eventStore.AddEventAsync(@event, cancellationToken).ConfigureAwait(false);
-                await OnEventSavedAsync(@event, cancellationToken).ConfigureAwait(false);
             }
 
             if (changeset.Snapshot != null)
             {
                 await _snapshotStore.AddSnapshotAsync(changeset.Snapshot, cancellationToken).ConfigureAwait(false);
-                await OnSnapshotSavedAsync(changeset.Snapshot, cancellationToken).ConfigureAwait(false);
             }
 
             changeset.Commit();
+            return changeset;
         }
 
-        protected virtual Task OnEventSavedAsync(IAggregateEvent<TKey> e,
-            CancellationToken cancellationToken = default) => Task.CompletedTask;
-
-        protected virtual Task OnSnapshotSavedAsync(IAggregateSnapshot<TKey> snapshot,
-            CancellationToken cancellationToken = default) => Task.CompletedTask;
-
         protected Task<TKey[]> GetAggregateIdsAsync()
         {
             return _eventStore.GetAggregateIdsAsync();