diff --git a/hosts/containers/hydra/hydra.nix b/hosts/containers/hydra/hydra.nix
index 5c36a2df..99439413 100644
--- a/hosts/containers/hydra/hydra.nix
+++ b/hosts/containers/hydra/hydra.nix
@@ -1,7 +1,7 @@
-{ config, pkgs, ... }:
+{ hostRegistry, config, pkgs, ... }:
 
 let
-  nix-build = "client@172.22.99.156";
+  nix-build = "client@${hostRegistry.hosts.nix-build.ip4}";
 in {
   nix = {
     binaryCaches =