diff --git a/arch-nspawn.in b/arch-nspawn.in
index b5fcc9d..5c0f46f 100644
--- a/arch-nspawn.in
+++ b/arch-nspawn.in
@@ -9,8 +9,7 @@
 # GNU General Public License for more details.
 
 m4_include(lib/common.sh)
-
-CHROOT_VERSION='v4'
+m4_include(lib/archroot.sh)
 
 working_dir=''
 
diff --git a/lib/archroot.sh b/lib/archroot.sh
new file mode 100644
index 0000000..25e94fb
--- /dev/null
+++ b/lib/archroot.sh
@@ -0,0 +1 @@
+CHROOT_VERSION='v4'
diff --git a/mkarchroot.in b/mkarchroot.in
index c4bb51a..e03b4f9 100644
--- a/mkarchroot.in
+++ b/mkarchroot.in
@@ -9,8 +9,7 @@
 # GNU General Public License for more details.
 
 m4_include(lib/common.sh)
-
-CHROOT_VERSION='v4'
+m4_include(lib/archroot.sh)
 
 working_dir=''