diff --git a/system/letsencrypt/letsencrypt.info b/system/letsencrypt/letsencrypt.info
index dd14c3279b..597de85752 100644
--- a/system/letsencrypt/letsencrypt.info
+++ b/system/letsencrypt/letsencrypt.info
@@ -5,6 +5,6 @@ DOWNLOAD="https://github.com/certbot/certbot/archive/v0.24.0/certbot-0.24.0.tar.
 MD5SUM="62717533ca2def2577a7b64954d775fd"
 DOWNLOAD_x86_64=""
 MD5SUM_x86_64=""
-REQUIRES="configobj mock python-requests pytz python2-pythondialog zope.component pyrfc3339 psutil python-parsedatetime python-configargparse werkzeug ndg_httpsclient python-augeas pyparsing josepy"
+REQUIRES="configobj mock python-requests pytz python2-pythondialog zope.component pyrfc3339 psutil python-parsedatetime python-configargparse werkzeug ndg_httpsclient python-augeas pyparsing josepy funcsigs"
 MAINTAINER="Willy Sudiarto Raharjo"
 EMAIL="willysr@slackbuilds.org"