diff --git a/build-constraints.yaml b/build-constraints.yaml
index 390382ff..8592725c 100644
--- a/build-constraints.yaml
+++ b/build-constraints.yaml
@@ -250,7 +250,7 @@ packages:
         - lucid
         - osdkeys
         - pdfinfo
-        #- present Due to: https://github.com/nominolo/atto-lisp/issues/20
+        - present
         - pure-io
         # https://github.com/jgoerzen/testpack/issues/11
         #- scrobble GHC 7.10, for QuickCheck 2.8 via testpack