Also the category/categories for each SRFI need to be specified in the
manual metadata, but I recall you had a fairly complete list of those.

I'm using Heroku to host the server because they make it really easy and
free, but the code is not really tied to Heroku. Any server where we can
run Racket and PostgreSQL/MySQL should work with some setup. We could
make a Docker container but I don't know if it's worth the effort. I
gave up on the serverless (AWS Lambda / Google Cloud Functions) approach
because it's so easy to run Racket on Heroku. Serverless could still be
made to work but I don't think it would be any easier or cheaper.

Heroku can be set up to serve sites under a custom domain (e.g.
schemers.org) but I don't know if it matters. The current domain is
<our-server>.herokuapp.com which is what they give by default. On a
custom domain we'd need to figure out how to set up SSL so that https://
URLs work.