I just work on the forum from time to time so I can't speak much on the language - others have made a lot of changes, the biggest I can think of being using curly braces to create tables. Arc is the first Lisp I've used, and it turns out I'm not a Lisp-1 person. I like proper namespaces and hygienic macros. If I could only change three things about Arc, it would be those and improving error messages.

As far as the forum is concerned - I moved it into a separate folder to create a distinction between "applications" and "library" code. That was controversial. Also related, there's the skeleton of an app manager in progress that will allow creating web app skeletons, and I'm trying to get a plugin manager to work through Arc's hook system.

The end goal (in my head, at least) is that one could install Arc and Arc library code (and possibly language extensions) separately from applications (like the forum, a blog, or whatever you've created for yourself) and from application specific plugins.

The forum page templates have been consolidated so now there's a single page layout with a common UI, which uses HTML lists rather than tables, making page rendering a lot faster. I suspect there's still a lot of work that could be done along those lines - there's just no rational reason why rendering HTML should be as slow as it seems to be sometimes.

And I added some of the user-side features people keep complaining about on HN such as a dark mode, archival links and adjustable font size.