I spent a bit more time on the Groovy Mail Server. I am still unable to send to ProtonMail, which uses Postfix. I opened up a ticket and sent them a log from tshark, but they were not able to find anything wrong. A lot of people use Postfix. Not being able to send to Postfix might be a show stopper.
I will install iRedMail; the purpose is two-fold: 1. Try to get Groovy Mail Server working with Postfix (and later TLS), and 2. And just to try it out in general. I am currently using Apache James. The version I am using is getting old, and it is time to look at other options. I might go with a newer version, but I figured I should try something else too. Eventually the version of James I am using might not work on a future JDK.
I posted a command that you can use to generate passphrases on a Linux laptop. I also added a page about the core Clojure API. Slowly but surely I am making progress. I might look more at Simply Scheme, but I plan on focusing more on Clojure.