diff --git a/src/Equinox.MemoryStore/MemoryStore.fs b/src/Equinox.MemoryStore/MemoryStore.fs
index d108c205d..855a9bcca 100644
--- a/src/Equinox.MemoryStore/MemoryStore.fs
+++ b/src/Equinox.MemoryStore/MemoryStore.fs
@@ -37,7 +37,7 @@ type VolatileStore<'Format>() =
         events
 
     /// Attempts a synchronization operation - yields conflicting value if expectedCount does not match
-    member _.TrySync(streamName, _categoryName, _streamId, expectedCount, events): struct (bool * FsCodec.ITimelineEvent<'Format>[]) =
+    member _.TrySync(streamName, expectedCount, events): struct (bool * FsCodec.ITimelineEvent<'Format>[]) =
         // Where attempts overlap on the same stream, there's a race to raise the Committed event for each 'commit'
         // If we don't serialize the publishing of the events, its possible for handlers to observe the Events out of order
         // NOTE while a Channels based impl might offer better throughput at load, in practical terms serializing all Committed event notifications
@@ -47,6 +47,8 @@ type VolatileStore<'Format>() =
             let struct (succeeded, _) as outcome = trySync streamName expectedCount events
             if succeeded then committed.Trigger(FsCodec.StreamName.Internal.trust streamName, events)
             outcome
+    [<System.Obsolete "Will be removed in v5">]
+    member x.TrySync(streamName, _categoryName, _streamId, expectedCount, events): struct (bool * FsCodec.ITimelineEvent<'Format>[]) = x.TrySync(streamName, expectedCount, events)
 
 type private StoreCategory<'event, 'state, 'req, 'Format>(store: VolatileStore<'Format>, codec, fold, initial) =
     let fold s xs = (fold : System.Func<'state, 'event[], 'state>).Invoke(s, xs)
@@ -60,7 +62,7 @@ type private StoreCategory<'event, 'state, 'req, 'Format>(store: VolatileStore<'
             | xs -> return res xs.Length initial (decode xs) }
         member _.Sync(_log, categoryName, streamId, streamName, req, token, state, events, _ct) = task {
             let encoded = events |> Array.mapi (fun i e -> FsCodec.Core.TimelineEvent.Create(token.version + int64 i, codec.Encode(req, e)))
-            match store.TrySync(streamName, categoryName, streamId, int token.version, encoded) with
+            match store.TrySync(streamName, int token.version, encoded) with
             | true, streamEvents' ->
                 return SyncResult.Written (res streamEvents'.Length state events)
             | false, conflictingEvents ->