diff --git a/slides/k8s/cluster-upgrade.md b/slides/k8s/cluster-upgrade.md
index 6a40083f..fcf89145 100644
--- a/slides/k8s/cluster-upgrade.md
+++ b/slides/k8s/cluster-upgrade.md
@@ -101,6 +101,8 @@
 
 - Network controller, network policy controller
 
+- Container engine
+
 - Linux kernel
 
 ---