diff --git a/CHANGELOG b/CHANGELOG
index 350df79..9ce5b32 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,4 +1,4 @@
-0.5      -
+0.5      - Add example systemd timer and service units
 0.4      - Add email and code signing flat file certificate stores
 0.3      - Generate single file stores (Java and GNUTLS) using main OpenSSL
            store as source to avoid duplicates
diff --git a/systemd/update-pki.service b/systemd/update-pki.service
new file mode 100644
index 0000000..6e79d09
--- /dev/null
+++ b/systemd/update-pki.service
@@ -0,0 +1,12 @@
+[Unit]
+Description=Update PKI/TLS certificate store
+Documentation=man:make-ca(8)
+DefaultDependencies=no
+After=local-fs.target
+Before=shutdown.target
+
+[Service]
+Type=oneshot
+RemainAfterExit=yes
+ExecStart=/usr/sbin/make-ca -g
+
diff --git a/systemd/update-pki.timer b/systemd/update-pki.timer
new file mode 100644
index 0000000..12b3de0
--- /dev/null
+++ b/systemd/update-pki.timer
@@ -0,0 +1,10 @@
+[Unit]
+Description=Update PKI/TLS certificate store weekly
+
+[Timer]
+OnCalendar=Sun 02:00:00
+Persistent=true
+
+[Install]
+WantedBy=timers.target
+