Gwern was kind enough to assist by sending over the exact version numbers of all the Haskell libraries it depends on, and answering some questions about deployment. The version numbers turned out to be crucial to getting everything running.
IMO https://www.gwern.net/ is the ideal combination of style + ease of use (for the writer) + effective ways of organizing knowledge.
The whole thing is hosted out of an S3 bucket, so there's no server to manage and zero downtime. I've wondered if it'd be possible to use github pages for this purpose, since that would make it completely free. But it only takes a couple hours of work to get everything up and running. The biggest delay is waiting for haskell to compile all the libraries.