diff --git a/basis/tools/scaffold/scaffold.factor b/basis/tools/scaffold/scaffold.factor
index e995876f26..17df1a13f2 100644
--- a/basis/tools/scaffold/scaffold.factor
+++ b/basis/tools/scaffold/scaffold.factor
@@ -22,7 +22,9 @@ M: bad-developer-name summary
 
 <PRIVATE
 
-: vocab-root? ( string -- ? ) vocab-roots get member? ;
+: vocab-root? ( string -- ? )
+    trim-tail-separators
+    vocab-roots get member? ;
 
 : contains-dot? ( string -- ? ) ".." swap subseq? ;
 
diff --git a/core/vocabs/loader/loader.factor b/core/vocabs/loader/loader.factor
index 9c1dcaef18..6df810359d 100644
--- a/core/vocabs/loader/loader.factor
+++ b/core/vocabs/loader/loader.factor
@@ -22,6 +22,7 @@ SYMBOL: add-vocab-root-hook
 ] "vocabs.loader" add-startup-hook
 
 : add-vocab-root ( root -- )
+    trim-tail-separators
     [ vocab-roots get adjoin ]
     [ add-vocab-root-hook get-global call( root -- ) ] bi ;