diff --git a/app-proto/src/assembly.rs b/app-proto/src/assembly.rs
index a00081a..92eaa62 100644
--- a/app-proto/src/assembly.rs
+++ b/app-proto/src/assembly.rs
@@ -13,6 +13,11 @@ pub type ConstraintKey = usize;
 
 pub type ElementColor = [f32; 3];
 
+/* KLUDGE */
+// we should reconsider this design when we build a system for switching between
+// assemblies. at that point, we might want to switch to hierarchical keys,
+// where each each element has a key that identifies it within its assembly and
+// each assembly has a key that identifies it within the sesssion
 static NEXT_ELEMENT_SERIAL: AtomicU64 = AtomicU64::new(0);
 
 #[derive(Clone, PartialEq)]