And to be a little more specific (because I really like Arc), the releases are very rare, and minor at this point. I would be surprised if the Arc that was running HN was the latest released version of Arc, the news library notwithstanding.

For example, the latest release, Arc3.2, came out in 2018, and was relatively minor (http://arclanguage.org/item?id=20772). Arc 3.1 was released in 2009 (http://arclanguage.org/item?id=10254).