diff --git a/app/build_npms.py b/app/build_npms.py
index 877916be..3750c4bd 100644
--- a/app/build_npms.py
+++ b/app/build_npms.py
@@ -119,7 +119,9 @@ def command(ctx, include, exclude):
             # Originally we used the PEP 584 merge operator:
             # envs = {"CERC_NPM_AUTH_TOKEN": npm_registry_url_token} | ({"CERC_SCRIPT_DEBUG": "true"} if debug else {})
             # but that isn't available in Python 3.8 (default in Ubuntu 20) so for now we use dict.update:
-            envs = {"CERC_NPM_AUTH_TOKEN": npm_registry_url_token}
+            envs = {"CERC_NPM_AUTH_TOKEN": npm_registry_url_token,
+                    "LACONIC_HOSTED_CONFIG_FILE": "config-hosted.yml" # Convention used by our web app packages
+                    }
             envs.update({"CERC_SCRIPT_DEBUG": "true"} if debug else {})
             try:
                 docker.run(builder_js_image_name,