diff --git a/Lullaby/ServiceExtension.cs b/Lullaby/ServiceExtension.cs
index b98fe40..e2cf250 100644
--- a/Lullaby/ServiceExtension.cs
+++ b/Lullaby/ServiceExtension.cs
@@ -113,6 +113,7 @@ this WebApplicationBuilder webApplicationBuilder
                     $"{Assembly.GetExecutingAssembly().GetName().Name}.xml"
                 )
             );
+            swagger.SupportNonNullableReferenceTypes();
         });
 
         webApplicationBuilder.Services.AddProblemDetails();