diff --git a/src/node-protocol.lisp b/src/node-protocol.lisp
index 33477fe..021c175 100644
--- a/src/node-protocol.lisp
+++ b/src/node-protocol.lisp
@@ -1,6 +1,8 @@
 (in-package :cleric)
 
-(defconstant +pass-through+ 112)
+(eval-when (:compile-toplevel :load-toplevel :execute)
+  (defconstant +pass-through+ 112)
+  )
 
 (alexandria:define-constant +tock+
     (make-array 4 :element-type 'octet :initial-element 0)