Node.JS can use Custom Environment Variables configured through the Acquia Cloud User Interface. See https://docs.acquia.com/cloud-platform/manage/variables/ for additional information about creating Custom Environment Variables.
Using a custom environment variable in your javascript application hosted on our Node.JS service allows you to update these variables without having to run a new pipelines build or code deployment. This can be great for features that you tune in your app and have to adjust on the fly.
Setting a new environment variable will restart the container with the new variables in place. This can be resource intensive, try to avoid this during high traffic times.
This can also be a way to restarting a Node.JS container without running Pipelines