Top three questions I got at #railsworld: Q: Does Rails work on JRuby? A: Yes, for 20 years now. Q: Didn't JRuby already solve this? A: Yes. Q: Why aren't you speaking here? A: I tried. Ask the organizers.

I'll be hanging out at #railsworld in the hack space near the entry. Come on over to chat about JRuby, or claim a shirt if you're a current user or supporter!

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Very interesting day of discussions at #railsworld! Introduced a few folks to JRuby, talked with some current users I did not know, even found one shop that only does JRuby. A bit sad to see folks struggling with problems JRuby solves. Hard to get the word out!

Calling all JRubyists at #railsworld! I HAVE T-SHIRTS! If you are using JRuby or officially support it in your app or library, come find me Thursday! I have L, XL, and one 3XL left.

Hello #railsworld! I'm here at the event running office hours and teaching people how to run Rails on JRuby. Find me in the vendor pavilion and grab a sticker!

It's incredible the amount of hacking required to get Rails to run in parallel with Ractors (and it still isn't there yet) when JRuby has been running Rails in parallel for decades. #railsworld

It occurs to me now: with the JVM now supporting native function calls and memory via the FFM API, could we not potentially treat it as a C compiler backend?

Would you buy JRuby swag to help fund the project? We recently did a run of JRuby "bird" t-shirts that have been very popular, but that stuff is expensive to give away for a little startup like ours.

Brno is a lovely little city. Don't know why I didn't see it when I visited in 2012.

I think I'm going to enable the JVM vector API (SSE etc, we already ship some optimizations that use it) by default for JRuby. Convince me not to.

After all these years, I just got burned (almost) by having a CI job not actually fail when one of the steps failed. It involved a subprocess launch with no error check, so even if it bombed out the job stayed green. 😩 A friendly reminder to make sure your CI jobs can fail.

Slides from my Euruko 2026 talk "JRuby: Past, Present, and Future" are now uploaded. I believe the talks were also recorded, so hopefully video will follow soon. Great event, I hope to return for 2027 in Modena, Italy! buff.ly/paSd5t9

AI is now the largest single point of failure in the history of software development. I know tons of developers that can't even work without an agent now. It's shocking how quickly the industry has become totally dependent on a few companies' services.

I'm finding more and more that agent-driven developers *really* appreciate having a human validate what they submit. nobody wants to be the asshole in an OSS project and being honest and communicative goes a long way toward making a good patch.

Like clockwork, I go to a Ruby event and meet JRuby users I never knew about! Just today, three people who used JRuby at previous jobs and two more that currently have apps in production. Gotta figure out how to reach these folks without speaking at every Ruby conference! 🤣