diff --git a/holycow_backend/src/types.rs b/holycow_backend/src/types.rs
index 3b80b99..62c7745 100644
--- a/holycow_backend/src/types.rs
+++ b/holycow_backend/src/types.rs
@@ -12,11 +12,13 @@ use crate::schema;
 #[derive(Debug, Clone, FromSqlRow, AsExpression)]
 #[diesel(sql_type = sql::BigInt)]
 #[diesel(check_for_backend(Pg))]
+#[repr(transparent)]
 pub struct TelegramId(pub teloxide::types::ChatId);
 
 #[derive(Debug, Clone, FromSqlRow, AsExpression)]
 #[diesel(sql_type = schema::sql_types::WenglinT)]
 #[diesel(check_for_backend(Pg))]
+#[repr(transparent)]
 pub struct WengLinRating(pub skillratings::weng_lin::WengLinRating);
 
 #[derive(Debug, Clone, Queryable, QueryableByName, Identifiable, Selectable)]