diff --git a/src/signup.rs b/src/signup.rs
index 71e2369..ff6785f 100644
--- a/src/signup.rs
+++ b/src/signup.rs
@@ -180,6 +180,7 @@ pub(crate) async fn create_user(
         .unwrap() // safe to unwrap, we know the salt is valid
         .to_string();
 
+    // TODO: look into ULIDs for sortable identifiers that are UUID-compatible
     let id = Uuid::new_v4();
     let query = sqlx::query(CREATE_QUERY)
         .bind(id)