diff --git a/debian/postinst.ex b/debian/postinst
similarity index 92%
rename from debian/postinst.ex
rename to debian/postinst
index 3937af5..dd9254b 100644
--- a/debian/postinst.ex
+++ b/debian/postinst
@@ -31,6 +31,8 @@ case "$1" in
     ;;
 esac
 
+adduser --system --group --no-create-home --home=/var/lib/adsms --quiet adsms
+
 # dh_installdeb will replace this with shell code automatically
 # generated by other debhelper scripts.