diff --git a/Notesnook.API/Interfaces/ISyncItem.cs b/Notesnook.API/Interfaces/ISyncItem.cs
deleted file mode 100644
index 2858555..0000000
--- a/Notesnook.API/Interfaces/ISyncItem.cs
+++ /dev/null
@@ -1,43 +0,0 @@
-/*
-This file is part of the Notesnook Sync Server project (https://notesnook.com/)
-
-Copyright (C) 2023 Streetwriters (Private) Limited
-
-This program is free software: you can redistribute it and/or modify
-it under the terms of the Affero GNU General Public License as published by
-the Free Software Foundation, either version 3 of the License, or
-(at your option) any later version.
-
-This program is distributed in the hope that it will be useful,
-but WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-Affero GNU General Public License for more details.
-
-You should have received a copy of the Affero GNU General Public License
-along with this program.  If not, see <http://www.gnu.org/licenses/>.
-*/
-
-using System.Text.Json.Serialization;
-using MongoDB.Bson.Serialization.Attributes;
-using MongoDB.Bson.Serialization.Serializers;
-using Notesnook.API.Models;
-using Streetwriters.Common.Attributes;
-using Streetwriters.Common.Converters;
-using Streetwriters.Common.Interfaces;
-
-namespace Notesnook.API.Interfaces
-{
-    [BsonSerializer(typeof(ImpliedImplementationInterfaceSerializer<ISyncItem, SyncItem>))]
-    [JsonInterfaceConverter(typeof(InterfaceConverter<ISyncItem, SyncItem>))]
-    public interface ISyncItem
-    {
-        long DateSynced
-        {
-            get; set;
-        }
-
-        string UserId { get; set; }
-        string Algorithm { get; set; }
-        string IV { get; set; }
-    }
-}
diff --git a/Notesnook.API/Models/SyncItem.cs b/Notesnook.API/Models/SyncItem.cs
index 1416f22..fac0d1e 100644
--- a/Notesnook.API/Models/SyncItem.cs
+++ b/Notesnook.API/Models/SyncItem.cs
@@ -17,17 +17,21 @@ You should have received a copy of the Affero GNU General Public License
 along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
+using System;
 using System.ComponentModel.DataAnnotations;
 using System.Runtime.Serialization;
 using System.Text.Json.Serialization;
 using MongoDB.Bson;
+using MongoDB.Bson.IO;
+using MongoDB.Bson.Serialization;
 using MongoDB.Bson.Serialization.Attributes;
+using MongoDB.Bson.Serialization.Serializers;
 using Notesnook.API.Interfaces;
 
 namespace Notesnook.API.Models
 {
     [MessagePack.MessagePackObject]
-    public class SyncItem : ISyncItem
+    public class SyncItem
     {
         [IgnoreDataMember]
         [MessagePack.IgnoreMember]
@@ -110,6 +114,103 @@ namespace Notesnook.API.Models
         } = Algorithms.Default;
     }
 
+    public class SyncItemBsonSerializer : SerializerBase<SyncItem>
+    {
+        public override void Serialize(BsonSerializationContext context, BsonSerializationArgs args, SyncItem value)
+        {
+            var writer = context.Writer;
+            writer.WriteStartDocument();
+
+            if (value.Id != ObjectId.Empty)
+            {
+                writer.WriteName("_id");
+                writer.WriteObjectId(value.Id);
+            }
+
+            writer.WriteName("DateSynced");
+            writer.WriteInt64(value.DateSynced);
+
+            writer.WriteName("UserId");
+            writer.WriteString(value.UserId);
+
+            writer.WriteName("IV");
+            writer.WriteString(value.IV);
+
+            writer.WriteName("Cipher");
+            writer.WriteString(value.Cipher);
+
+            writer.WriteName("ItemId");
+            writer.WriteString(value.ItemId);
+
+            writer.WriteName("Length");
+            writer.WriteInt64(value.Length);
+
+            writer.WriteName("Version");
+            writer.WriteDouble(value.Version);
+
+            writer.WriteName("Algorithm");
+            writer.WriteString(value.Algorithm);
+
+            writer.WriteEndDocument();
+        }
+
+        public override SyncItem Deserialize(BsonDeserializationContext context, BsonDeserializationArgs args)
+        {
+            var bsonReader = context.Reader;
+            bsonReader.ReadStartDocument();
+
+            bsonReader.ReadBsonType();
+            bsonReader.SkipName();
+            var id = bsonReader.ReadObjectId();
+
+            bsonReader.ReadBsonType();
+            bsonReader.SkipName();
+            var dateSynced = bsonReader.ReadInt64();
+
+            bsonReader.ReadBsonType();
+            bsonReader.SkipName();
+            var userId = bsonReader.ReadString();
+
+            bsonReader.ReadBsonType();
+            bsonReader.SkipName();
+            var iv = bsonReader.ReadString();
+
+            bsonReader.ReadBsonType();
+            bsonReader.SkipName();
+            var cipher = bsonReader.ReadString();
+
+            bsonReader.ReadBsonType();
+            bsonReader.SkipName();
+            var itemId = bsonReader.ReadString();
+
+            bsonReader.ReadBsonType();
+            bsonReader.SkipName();
+            var length = bsonReader.ReadInt64();
+
+            bsonReader.ReadBsonType();
+            bsonReader.SkipName();
+            var version = bsonReader.ReadDouble();
+
+            bsonReader.ReadBsonType();
+            bsonReader.SkipName();
+            var algorithm = bsonReader.ReadString();
+
+            bsonReader.ReadEndDocument();
+            return new SyncItem
+            {
+                Id = id,
+                DateSynced = dateSynced,
+                UserId = userId,
+                IV = iv,
+                Cipher = cipher,
+                ItemId = itemId,
+                Length = length,
+                Version = version,
+                Algorithm = algorithm
+            };
+        }
+    }
+
     [MessagePack.MessagePackObject]
     public class SettingItem : SyncItem { }
 
diff --git a/Notesnook.API/Startup.cs b/Notesnook.API/Startup.cs
index fe1cfd6..8932f4b 100644
--- a/Notesnook.API/Startup.cs
+++ b/Notesnook.API/Startup.cs
@@ -159,6 +159,7 @@ namespace Notesnook.API
                 options.CacheDuration = TimeSpan.FromMinutes(30);
             });
 
+            BsonSerializer.RegisterSerializer(new SyncItemBsonSerializer());
             if (!BsonClassMap.IsClassMapRegistered(typeof(UserSettings)))
                 BsonClassMap.RegisterClassMap<UserSettings>();