Related:

HelenOS 0.8 - https://news.ycombinator.com/item?id=18833124 - Jan 2019 (55 comments)

HelenOS: portable microkernel-based multiserver operating system - https://news.ycombinator.com/item?id=15046249 - Aug 2017 (67 comments)

Thanks! also this one I guess:

HelenOS GUI – experimental demonstration (2012) - https://news.ycombinator.com/item?id=12784350 - Oct 2016 (12 comments)

p.s. nice formatting. (I want to add software to offer to inline HN links in this format when people include links to past threads in their comments.)

https://github.com/plibither8/refined-hacker-news

Install this and than look at the bottom of the page. :-D