diff --git a/racket/collects/acks/acks.rkt b/racket/collects/acks/acks.rkt
index d53d196ad4..cd9dbc61b2 100644
--- a/racket/collects/acks/acks.rkt
+++ b/racket/collects/acks/acks.rkt
@@ -51,6 +51,7 @@
    "Shriram Krishnamurthi, "
    "Mario Latendresse, "
    "Guillaume Marceau, "
+   "Gustavo Massaccesi, "
    "Jacob Matthews, "
    "Jay McCarthy, "
    "Mike T. McHenry, "