diff --git a/nix/docker/vault/default.nix b/nix/docker/vault/default.nix
index 24741fccda..ef7f91b2d7 100644
--- a/nix/docker/vault/default.nix
+++ b/nix/docker/vault/default.nix
@@ -27,7 +27,7 @@ let
     name = imageName;
     tag = imageVersion;
 
-    contents = pluginDrv;
+    copyToRoot = pluginDrv;
 
     # Using vault-bin because I want the vault UI.
     config.Entrypoint = [ "${vault}/bin/vault" "server" "-config" "/etc/vault/config.hcl" ];