diff --git a/crates/cli/src/subcommands/generate/csharp.rs b/crates/cli/src/subcommands/generate/csharp.rs
index c53f4e7126b..6148a411d8f 100644
--- a/crates/cli/src/subcommands/generate/csharp.rs
+++ b/crates/cli/src/subcommands/generate/csharp.rs
@@ -407,20 +407,20 @@ fn autogen_csharp_access_funcs_for_struct(
             None => continue,
             Some(x) => x,
         };
-        writeln!(
-            output,
-            "public readonly ref struct {csharp_field_name_pascal}UniqueIndex"
-        );
+        writeln!(output, "public class {csharp_field_name_pascal}UniqueIndex");
         indented_block(output, |output| {
+            write!(
+                output,
+                "internal readonly Dictionary<{csharp_field_type}, {struct_name_pascal_case}> Cache = new(16);"
+            );
+            writeln!(output);
+
             writeln!(
                 output,
                 "public {struct_name_pascal_case}? Find({csharp_field_type} value)"
             );
             indented_block(output, |output| {
-                writeln!(
-                    output,
-                    "{csharp_field_name_pascal}_Index.TryGetValue(value, out var r);"
-                );
+                writeln!(output, "Cache.TryGetValue(value, out var r);");
                 writeln!(output, "return r;");
             });
             writeln!(output);
@@ -428,7 +428,7 @@ fn autogen_csharp_access_funcs_for_struct(
         writeln!(output);
         writeln!(
             output,
-            "public {csharp_field_name_pascal}UniqueIndex {csharp_field_name_pascal} => new();"
+            "public {csharp_field_name_pascal}UniqueIndex {csharp_field_name_pascal} = new();"
         );
         writeln!(output);
     }
@@ -589,11 +589,6 @@ pub fn autogen_csharp_globals(ctx: &GenCtx, items: &[GenItem], namespace: &str)
                     if !constraints[&ColList::new(col.col_pos)].has_unique() {
                         continue;
                     }
-                    let type_name = ty_fmt(ctx, &col.col_type, namespace);
-                    writeln!(
-                        output,
-                        "private static Dictionary<{type_name}, {table_type}> {field_name}_Index = new(16);"
-                    );
                     unique_indexes.push(field_name);
                 }
                 if !unique_indexes.is_empty() {
@@ -610,7 +605,7 @@ pub fn autogen_csharp_globals(ctx: &GenCtx, items: &[GenItem], namespace: &str)
                             if !constraints[&ColList::new(col.col_pos)].has_unique() {
                                 continue;
                             }
-                            writeln!(output, "{field_name}_Index[value.{field_name}] = value;");
+                            writeln!(output, "{field_name}.Cache[value.{field_name}] = value;");
                         }
                     });
                     writeln!(output);
@@ -625,7 +620,7 @@ pub fn autogen_csharp_globals(ctx: &GenCtx, items: &[GenItem], namespace: &str)
                             if !constraints[&ColList::new(col.col_pos)].has_unique() {
                                 continue;
                             }
-                            writeln!(output, "{field_name}_Index.Remove((({table_type})row).{field_name});");
+                            writeln!(output, "{field_name}.Cache.Remove((({table_type})row).{field_name});");
                         }
                     });
                     writeln!(output);
diff --git a/crates/cli/tests/snapshots/codegen__codegen_csharp.snap b/crates/cli/tests/snapshots/codegen__codegen_csharp.snap
index 163116ed327..2095776370a 100644
--- a/crates/cli/tests/snapshots/codegen__codegen_csharp.snap
+++ b/crates/cli/tests/snapshots/codegen__codegen_csharp.snap
@@ -672,45 +672,45 @@ namespace SpacetimeDB
 
 		public class PkMultiIdentityHandle : RemoteTableHandle<EventContext, PkMultiIdentity>
 		{
-			private static Dictionary<uint, PkMultiIdentity> Id_Index = new(16);
-			private static Dictionary<uint, PkMultiIdentity> Other_Index = new(16);
 
 			public override void InternalInvokeValueInserted(IDatabaseRow row)
 			{
 				var value = (PkMultiIdentity)row;
-				Id_Index[value.Id] = value;
-				Other_Index[value.Other] = value;
+				Id.Cache[value.Id] = value;
+				Other.Cache[value.Other] = value;
 			}
 
 			public override void InternalInvokeValueDeleted(IDatabaseRow row)
 			{
-				Id_Index.Remove(((PkMultiIdentity)row).Id);
-				Other_Index.Remove(((PkMultiIdentity)row).Other);
+				Id.Cache.Remove(((PkMultiIdentity)row).Id);
+				Other.Cache.Remove(((PkMultiIdentity)row).Other);
 			}
 
-			public readonly ref struct IdUniqueIndex
+			public class IdUniqueIndex
 			{
+				internal readonly Dictionary<uint, PkMultiIdentity> Cache = new(16);
 				public PkMultiIdentity? Find(uint value)
 				{
-					Id_Index.TryGetValue(value, out var r);
+					Cache.TryGetValue(value, out var r);
 					return r;
 				}
 
 			}
 
-			public IdUniqueIndex Id => new();
+			public IdUniqueIndex Id = new();
 
-			public readonly ref struct OtherUniqueIndex
+			public class OtherUniqueIndex
 			{
+				internal readonly Dictionary<uint, PkMultiIdentity> Cache = new(16);
 				public PkMultiIdentity? Find(uint value)
 				{
-					Other_Index.TryGetValue(value, out var r);
+					Cache.TryGetValue(value, out var r);
 					return r;
 				}
 
 			}
 
-			public OtherUniqueIndex Other => new();
+			public OtherUniqueIndex Other = new();
 
 			internal PkMultiIdentityHandle()
 			{
@@ -754,30 +754,30 @@ namespace SpacetimeDB
 
 		public class RepeatingTestArgHandle : RemoteTableHandle<EventContext, RepeatingTestArg>
 		{
-			private static Dictionary<ulong, RepeatingTestArg> ScheduledId_Index = new(16);
 
 			public override void InternalInvokeValueInserted(IDatabaseRow row)
 			{
 				var value = (RepeatingTestArg)row;
-				ScheduledId_Index[value.ScheduledId] = value;
+				ScheduledId.Cache[value.ScheduledId] = value;
 			}
 
 			public override void InternalInvokeValueDeleted(IDatabaseRow row)
 			{
-				ScheduledId_Index.Remove(((RepeatingTestArg)row).ScheduledId);
+				ScheduledId.Cache.Remove(((RepeatingTestArg)row).ScheduledId);
 			}
 
-			public readonly ref struct ScheduledIdUniqueIndex
+			public class ScheduledIdUniqueIndex
 			{
+				internal readonly Dictionary<ulong, RepeatingTestArg> Cache = new(16);
 				public RepeatingTestArg? Find(ulong value)
 				{
-					ScheduledId_Index.TryGetValue(value, out var r);
+					Cache.TryGetValue(value, out var r);
 					return r;
 				}
 
 			}
 
-			public ScheduledIdUniqueIndex ScheduledId => new();
+			public ScheduledIdUniqueIndex ScheduledId = new();
 
 			internal RepeatingTestArgHandle()
 			{
@@ -821,30 +821,30 @@ namespace SpacetimeDB
 
 		public class TestEHandle : RemoteTableHandle<EventContext, TestE>
 		{
-			private static Dictionary<ulong, TestE> Id_Index = new(16);
 
 			public override void InternalInvokeValueInserted(IDatabaseRow row)
 			{
 				var value = (TestE)row;
-				Id_Index[value.Id] = value;
+				Id.Cache[value.Id] = value;
 			}
 
 			public override void InternalInvokeValueDeleted(IDatabaseRow row)
 			{
-				Id_Index.Remove(((TestE)row).Id);
+				Id.Cache.Remove(((TestE)row).Id);
 			}
 
-			public readonly ref struct IdUniqueIndex
+			public class IdUniqueIndex
 			{
+				internal readonly Dictionary<ulong, TestE> Cache = new(16);
 				public TestE? Find(ulong value)
 				{
-					Id_Index.TryGetValue(value, out var r);
+					Cache.TryGetValue(value, out var r);
 					return r;
 				}
 
 			}
 
-			public IdUniqueIndex Id => new();
+			public IdUniqueIndex Id = new();
 
 			public class NameIndex
 			{