diff --git a/emacs/notmuch-maildir-fcc.el b/emacs/notmuch-maildir-fcc.el
index ae8f5140..c715532b 100644
--- a/emacs/notmuch-maildir-fcc.el
+++ b/emacs/notmuch-maildir-fcc.el
@@ -21,6 +21,8 @@
 
 ;;; Code:
 
+(require 'seq)
+
 (require 'message)
 
 (require 'notmuch-lib)