diff --git a/PORTING-TO-DO b/PORTING-TO-DO
index 6b5ecbb..c21639f 100644
--- a/PORTING-TO-DO
+++ b/PORTING-TO-DO
@@ -9,3 +9,4 @@
 
 - (ryanc) add (or find?) sxml-top?, sxml-element?, etc predicates
 - (ryanc) parameters and/or kw args for continuable errors / warnings
+- (ryanc) parameters for defaults, eg namespace-abbreviations