diff --git a/metropolis/test/util/rpc.go b/metropolis/test/util/rpc.go
index 030d8d0..c31c935 100644
--- a/metropolis/test/util/rpc.go
+++ b/metropolis/test/util/rpc.go
@@ -66,7 +66,7 @@
 		nodeCert := pki.Certificate{
 			Namespace: &ns,
 			Issuer:    &caCert,
-			Template:  identity.NodeCertificate(npk),
+			Template:  identity.NodeCertificate(identity.NodeID(npk)),
 			Mode:      pki.CertificateEphemeral,
 			PublicKey: npk,
 			Name:      "",