diff --git a/jupyter-channel.el b/jupyter-channel.el
index 1d1719ff..c9e7e653 100644
--- a/jupyter-channel.el
+++ b/jupyter-channel.el
@@ -25,6 +25,7 @@
 ;; Defines the `jupyter-channel' interface.
 
 ;;; Code:
+(require 'eieio-base)
 
 (defclass jupyter-channel ()
   ((type