OppenServer

The server you're reading this content on is a node.js project that serves both web and gemini content from the same Gemtext source files:

It's very easy to setup, assuming you have access to your web certificate to serve content on port 443, and a suitable TLS certificate for serving Gemini on port 1965.

Gemini requests are handled by simply serving files (after sanitising the path request), web requests look for an index.gmi file to convert to html that's then wrapped with a static header and footer.