--- a/configure.ac.old	2017-07-24 17:44:11.647249254 +0200
+++ b/configure.ac	2017-07-24 17:46:00.917734203 +0200
@@ -265,8 +265,12 @@
 CPPFLAGS="$old_CPPFLAGS"
 LIBS="$old_LIBS"
 
-PKG_CHECK_MODULES([SYSTEMD], [libsystemd >= 209], [USE_SD_NOTIFY=1], [USE_SD_NOTIFY=0])
-AC_SUBST(USE_SD_NOTIFY)
+AC_ARG_ENABLE([systemd], AS_HELP_STRING([--enable-systemd], [Enable systemd notify support (default: disabled)]))
+
+AS_IF([test "x$enable_systemd" = "xyes"], [
+  PKG_CHECK_MODULES([SYSTEMD], [libsystemd >= 209], [USE_SD_NOTIFY=1], [USE_SD_NOTIFY=0])
+  AC_SUBST(USE_SD_NOTIFY)
+])
 
 AC_CHECK_LIB(resolv, res_gethostbyname, RESOLV="-lresolv", RESOLV="")
 if test x$RESOLV != x