From fe4960cec5e31b8cc8cd332d138dee7b894fe9d7 Mon Sep 17 00:00:00 2001
From: Anne Erdtsieck <anne.erdtsieck@topicus.nl>
Date: Fri, 24 Jan 2025 17:59:15 +0100
Subject: [PATCH] #3636 live projection should not call ApplyChangesAsync/store

---
 src/Marten/Events/Aggregation/CustomProjection.cs | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/src/Marten/Events/Aggregation/CustomProjection.cs b/src/Marten/Events/Aggregation/CustomProjection.cs
index 5434135d18..bff1881c72 100644
--- a/src/Marten/Events/Aggregation/CustomProjection.cs
+++ b/src/Marten/Events/Aggregation/CustomProjection.cs
@@ -376,9 +376,15 @@ async ValueTask<TDoc> ILiveAggregator<TDoc>.BuildAsync(IReadOnlyList<IEvent> eve
         var documentSessionBase = session as DocumentSessionBase ?? (DocumentSessionBase)session.DocumentStore.LightweightSession();
 
         var slice = new EventSlice<TDoc, TId>(default, session, events);
-        await ApplyChangesAsync(documentSessionBase, slice, cancellation).ConfigureAwait(false);
-
-        ApplyMetadata(slice.Aggregate, events.Last());
+        if (Lifecycle == ProjectionLifecycle.Live)
+        {
+            slice.Aggregate = await BuildAsync(session, slice.Aggregate, slice.Events()).ConfigureAwait(false);
+            ApplyMetadata(slice.Aggregate, events.Last());
+        }
+        else
+        {
+            await ApplyChangesAsync(documentSessionBase, slice, cancellation).ConfigureAwait(false);
+        }
 
         return slice.Aggregate;
     }