utilum started committing to Rails in 2016 and is still at it today. Their GitHub is completely devoid of biographical info, so I’ll respect their apparent desire for anonymity. They’re prolific; they’ve made commits to ActiveSupport, ActiveStorage, ActionPack, ActiveRecord, ActionCable, ActionView, and ActiveJob. “update” and “version” are two of the most commonly-used words in their commits, and many of their contributions have fixed warnings, cleaned up old code paths, and upgraded various dependencies. utilum appears to work in deliberate obscurity while fixing all the little details that would otherwise trigger warnings and make Rails less of a smooth, pleasurable dev experience. That’s pretty awesome and it’s probably made my life better many times. So, thank you utilum.
Juanito Fatas contributed to Rails for five years, from 2013 to 2018. His GitHub says that he’s taking a break right now, and it looks like he’s really earned it. Although he’s contributed bugfixes as well, the bulk of his work has been in the Rails guides. Only 22 of his 97 commits were outside the guides; the remaining 75 were all documentation commits. I know I’ve relied on the Rails Guides countless times, and this is true for a huge number of other developers as well. So a big thank you to Juanito for putting in so much work making the Rails documentation top-notch.