the rendered meta flake pins hyperhive by forge URL and follows its nixpkgs

nix/module-eval/builder.nix

@@ -135,8 +135,8 @@ let
         && lib.elem "swarm-bao-pki.service" c.after;
     }
     {
-      # The check builds on the sources a hive on this host would render into
-      # its meta flake, so a green check means the same base.
+      # The check builds on the sources this host was deployed with, so a green check means
+      # the same hyperhive, docs and nixpkgs base.
       name = "the builder builds on the hyperhive, docs and nixpkgs this host's hives use";
       ok =
         env.SWARM_BUILDER_HYPERHIVE_FLAKE == withBuilder.services.hyperhive.c0re.hyperhiveFlake