I published an article about Zettelkästen: https://github.com/alefore/weblog/blob/master/zettelkasten.m...
I'm also working on an article about software correctness, summarizing my experience working on infrastructure software at Google for about 13 years. It's very incomplete and I'll probably end up restructuring it significantly (not very happy with the current logical structure). I only started working on this two or three weeks ago (as a side project), so I'm satisfied with the progress I've been able to make: https://github.com/alefore/weblog/blob/master/software-corre...
I'm also working on other similar articles on other topics (Bitcoin, Stoicism, Bauhaus), but those are even less complete.
Lastly, I've continued to make significant improvements to my text editor (https://github.com/alefore/edge).
I think it's interesting that I'm finding it hard to focus on some topics, but I'm currently very productive in others.