diff --git a/CapnpC.CSharp.Generator/CodeGen/GeneratorOptions.cs b/CapnpC.CSharp.Generator/CodeGen/GeneratorOptions.cs
index a8ec763..c6516bb 100644
--- a/CapnpC.CSharp.Generator/CodeGen/GeneratorOptions.cs
+++ b/CapnpC.CSharp.Generator/CodeGen/GeneratorOptions.cs
@@ -34,6 +34,6 @@
         public string MemberAccessPathNameFormat { get; set; } = "Path_{0}_{1}";
         public string TaskParameterName { get; set; } = "task";
         public string EagerMethodName { get; set; } = "Eager";
-        public string TypeIdFieldName { get; set; } = "TypeId";
+        public string TypeIdFieldName { get; set; } = "typeId";
     }
 }