diff --git a/packages/cultnet-py/tools/GameCult.Caching.Benchmark/Program.cs b/packages/cultnet-py/tools/GameCult.Caching.Benchmark/Program.cs
index e5f9d5fd..14ec8d5e 100644
--- a/packages/cultnet-py/tools/GameCult.Caching.Benchmark/Program.cs
+++ b/packages/cultnet-py/tools/GameCult.Caching.Benchmark/Program.cs
@@ -94,6 +94,7 @@ internal sealed record BenchmarkResult(string Runtime, int Records, IReadOnlyLis
 internal sealed record BenchmarkMetric(string Name, int Operations, double ElapsedMs, double OpsPerSecond);
 
 [CultDocument("bench.item", "bench.item.v1")]
+[MessagePackObject(AllowPrivate = true)]
 internal sealed class BenchItem
 {
     [Key(0)] [CultName]
diff --git a/src/GameCult.Mesh/CultMeshSimulationFacts.cs b/src/GameCult.Mesh/CultMeshSimulationFacts.cs
index 6efa8711..11c7d296 100644
--- a/src/GameCult.Mesh/CultMeshSimulationFacts.cs
+++ b/src/GameCult.Mesh/CultMeshSimulationFacts.cs
@@ -13,6 +13,7 @@ namespace GameCult.Mesh
     /// Committed simulation fact derived from witness consensus.
     /// </summary>
     [CultDocument("gamecult.mesh.simulation_fact", "gamecult.mesh.simulation_fact.v1")]
+    [MessagePackObject]
     public sealed class CultMeshSimulationFact
     {
         /// <summary>
diff --git a/src/GameCult.Networking/PlayerData.cs b/src/GameCult.Networking/PlayerData.cs
index 997db848..ade82c0f 100644
--- a/src/GameCult.Networking/PlayerData.cs
+++ b/src/GameCult.Networking/PlayerData.cs
@@ -8,6 +8,7 @@ namespace GameCult.Networking
     /// Basic player account document used by the sample networking stack.
     /// </summary>
     [CultDocument("gamecult.player_data", "gamecult.player_data.v2")]
+    [MessagePackObject]
     public class PlayerData
     {
         /// <summary>
diff --git a/tests/GameCult.Caching.Tests/ConditionalCommitTests.cs b/tests/GameCult.Caching.Tests/ConditionalCommitTests.cs
index 875d7664..adfd67e3 100644
--- a/tests/GameCult.Caching.Tests/ConditionalCommitTests.cs
+++ b/tests/GameCult.Caching.Tests/ConditionalCommitTests.cs
@@ -911,6 +911,7 @@ namespace GameCult.Caching.Tests
         }
 
         [CultDocument("tests.conditional_counter", "tests.conditional_counter.v1")]
+        [MessagePackObject(AllowPrivate = true)]
         internal sealed class Counter
         {
             [Key(0)]
@@ -922,6 +923,7 @@ namespace GameCult.Caching.Tests
         }
 
         [CultDocument("tests.conditional_tally", "tests.conditional_tally.v1")]
+        [MessagePackObject(AllowPrivate = true)]
         internal sealed class Tally
         {
             [Key(0)]
@@ -931,14 +933,15 @@ namespace GameCult.Caching.Tests
 
         // Loading a record with Blocks set waits on Pause, which parks a directory pull inside its page load.
         [CultDocument("tests.conditional_slow", "tests.conditional_slow.v1")]
+        [MessagePackObject(AllowPrivate = true)]
         internal sealed class Slow
         {
             internal static volatile ManualResetEventSlim? Pause;
             internal static readonly ManualResetEventSlim Entered = new();
             internal static volatile bool Paused;
             internal static volatile bool ReadWhilePaused;
-            private bool _blocks;
-            private string _name = string.Empty;
+            [IgnoreMember] private bool _blocks;
+            [IgnoreMember] private string _name = string.Empty;
 
             [Key(0)]
             [CultName]
diff --git a/tests/GameCult.Caching.Tests/DirectoryStoreDurabilityTests.cs b/tests/GameCult.Caching.Tests/DirectoryStoreDurabilityTests.cs
index 473717cc..41ef46ad 100644
--- a/tests/GameCult.Caching.Tests/DirectoryStoreDurabilityTests.cs
+++ b/tests/GameCult.Caching.Tests/DirectoryStoreDurabilityTests.cs
@@ -228,6 +228,7 @@ namespace GameCult.Caching.Tests
             Path.Combine(_records, BitConverter.ToString(identity).Replace("-", string.Empty).ToLowerInvariant() + ".msgpack");
 
         [CultDocument("tests.durability_page", "tests.durability_page.v1")]
+        [MessagePackObject(AllowPrivate = true)]
         internal sealed class Page
         {
             [Key(0)]
diff --git a/tests/GameCult.Caching.Tests/PreCut2FixtureDocuments.cs b/tests/GameCult.Caching.Tests/PreCut2FixtureDocuments.cs
index 4598b7a5..9f9ab7dc 100644
--- a/tests/GameCult.Caching.Tests/PreCut2FixtureDocuments.cs
+++ b/tests/GameCult.Caching.Tests/PreCut2FixtureDocuments.cs
@@ -4,6 +4,7 @@ using MessagePack;
 namespace GameCult.Caching.Tests
 {
     [CultDocument("fixtures.precut2.item", "fixtures.precut2.item.v1")]
+    [MessagePackObject(AllowPrivate = true)]
     internal sealed class PreCut2FixtureItem
     {
         [Key(0)]
@@ -15,6 +16,7 @@ namespace GameCult.Caching.Tests
     }
 
     [CultDocument("fixtures.precut2.note", "fixtures.precut2.note.v1")]
+    [MessagePackObject(AllowPrivate = true)]
     internal sealed class PreCut2FixtureNote
     {
         [Key(0)]
diff --git a/tests/GameCult.Caching.Tests/StoreRoutingTests.cs b/tests/GameCult.Caching.Tests/StoreRoutingTests.cs
index 31619292..9a65dc89 100644
--- a/tests/GameCult.Caching.Tests/StoreRoutingTests.cs
+++ b/tests/GameCult.Caching.Tests/StoreRoutingTests.cs
@@ -707,6 +707,7 @@ namespace GameCult.Caching.Tests
         }
 
         [CultDocument("tests.routing_note", "tests.routing_note.v1")]
+        [MessagePackObject(AllowPrivate = true)]
         internal sealed class RoutingNote
         {
             [Key(0)]
@@ -718,6 +719,7 @@ namespace GameCult.Caching.Tests
         }
 
         [CultDocument("tests.routing_other", "tests.routing_other.v1")]
+        [MessagePackObject(AllowPrivate = true)]
         internal sealed class RoutingOther
         {
             [Key(0)]
@@ -729,6 +731,7 @@ namespace GameCult.Caching.Tests
         }
 
         [CultDocument("tests.routing_gear", "tests.routing_gear.v1")]
+        [MessagePackObject]
         public class RoutingGear
         {
             [Key(0)]
@@ -736,6 +739,7 @@ namespace GameCult.Caching.Tests
         }
 
         [CultDocument("tests.routing_weapon", "tests.routing_weapon.v1")]
+        [MessagePackObject]
         public sealed class RoutingWeapon : RoutingGear
         {
             [Key(1)]
@@ -747,6 +751,7 @@ namespace GameCult.Caching.Tests
         }
 
         [CultDocument("tests.routing_leaf", "tests.routing_leaf.v1")]
+        [MessagePackObject(AllowPrivate = true)]
         internal sealed class RoutingLeaf : RoutingBase
         {
             [Key(0)]
@@ -755,6 +760,7 @@ namespace GameCult.Caching.Tests
         }
 
         [CultDocument("tests.routing_leaf_twin", "tests.routing_leaf_twin.v1")]
+        [MessagePackObject(AllowPrivate = true)]
         internal sealed class RoutingLeafTwin : RoutingBase
         {
             [Key(0)]
@@ -767,6 +773,7 @@ namespace GameCult.Caching.Tests
         }
 
         [CultDocument("tests.routing_global", "tests.routing_global.v1")]
+        [MessagePackObject(AllowPrivate = true)]
         [CultGlobal]
         internal sealed class RoutingGlobal : RoutingGlobalBase
         {
diff --git a/tests/GameCult.Networking.InteropPeer/Program.cs b/tests/GameCult.Networking.InteropPeer/Program.cs
index 953ee097..d4c8fab7 100644
--- a/tests/GameCult.Networking.InteropPeer/Program.cs
+++ b/tests/GameCult.Networking.InteropPeer/Program.cs
@@ -1490,6 +1490,7 @@ static class InteropPeerShared
 }
 
 [CultDocument(InteropPeerShared.InteropDocumentType, InteropPeerShared.InteropSchemaVersion)]
+[MessagePackObject]
 public sealed class CultNetInteropNote
 {
     [Key(0)] public string SchemaVersion { get; set; } = InteropPeerShared.InteropSchemaVersion;