Hey, Substack CTO here. We're actually not using Ghost's platform and have instead built a theming API that is compatible with third-party themes that are built

Hey, Substack CTO here. We're actually not using Ghost's platform and have instead built a theming API that is compatible with third-party themes that are built for Ghost. The one piece of code that the theme uses that's developed by Ghost is the open source search library used on the frontend. In this case the theme links directly to the files that Ghost has distributed on jsdelivr via npm