diff --git a/debian/freeipa-client-epn.install b/debian/freeipa-client-epn.install
index b3a99b2..7edc5e2 100644
--- a/debian/freeipa-client-epn.install
+++ b/debian/freeipa-client-epn.install
@@ -1,7 +1,7 @@
 etc/ipa/epn.conf
 etc/ipa/epn/expire_msg.template
-${env:systemdsystemunitdir}/ipa-epn.service
-${env:systemdsystemunitdir}/ipa-epn.timer
+@systemdsystemunitdir@/ipa-epn.service
+@systemdsystemunitdir@/ipa-epn.timer
 usr/sbin/ipa-epn
 usr/share/man/man1/ipa-epn.1
 usr/share/man/man5/epn.conf.5
diff --git a/debian/rules b/debian/rules
index 1946382..9e0423f 100755
--- a/debian/rules
+++ b/debian/rules
@@ -20,13 +20,12 @@ DESTDIR=$(CURDIR)/debian/tmp
 export PYTHON=python3
 export am_cv_python_pythondir=/usr/lib/python3/dist-packages
 export am_cv_python_pyexecdir=/usr/lib/python3/dist-packages
-#export systemdsystemunitdir=$(shell pkgconf --variable=systemdsystemunitdir systemd | sed s,^/,,)
 
+# Detect systemd unit dir with fallback
 systemdsystemunitdir := $(shell pkgconf --variable=systemdsystemunitdir systemd 2>/dev/null | sed 's,^/,,')
 ifeq ($(systemdsystemunitdir),)
 systemdsystemunitdir := lib/systemd/system
 endif
-
 export systemdsystemunitdir
 
 confflags = \
@@ -132,6 +131,7 @@ override_dh_fixperms:
 	fi
 
 override_dh_gencontrol:
+	echo "systemdsystemunitdir=$(systemdsystemunitdir)" >> debian/substvars
 	dh_gencontrol -- \
 	  -Vlib:Depends=$(shell dpkg-query -W -f '$${Depends}' librpm-dev \
 			| sed -E 's/.*(librpm[[:alnum:].-]+).*/\1/')