diff --git a/Cask b/Cask
index f556a52..7951e4b 100644
--- a/Cask
+++ b/Cask
@@ -10,5 +10,6 @@
 
 (development
  (depends-on "ert-runner")
+ (depends-on "zmq")
  (depends-on "org-plus-contrib")
  (depends-on "julia-mode"))