Joshua Young
@joshuay03.bsky.social
Software Engineer at Buildkite, Rubyist, Rails Issues team member, Puma maintainer, and OSS contributor.
I really shouldn't be sharing teasers given how much work's left to do, and the good chance that this becomes another forgotten experiment, but I'm pretty happy with how far I got with barely any tuning (compared to the 20-year battle-tested Puma, which I've taken some inspiration from <3).
1/5
1/5
November 10, 2025 at 5:44 PM
I really shouldn't be sharing teasers given how much work's left to do, and the good chance that this becomes another forgotten experiment, but I'm pretty happy with how far I got with barely any tuning (compared to the 20-year battle-tested Puma, which I've taken some inspiration from <3).
1/5
1/5
Announcing RactorPool: github.com/joshuay03/ra...
Extracted from a project I'm building with Ractors. Currently requires Ruby 3.5 (3.5.0.dev). Goal is to have it stable for Ruby 4.0, when Ractors will be less experimental 🤞🏽
Extracted from a project I'm building with Ractors. Currently requires Ruby 3.5 (3.5.0.dev). Goal is to have it stable for Ruby 4.0, when Ractors will be less experimental 🤞🏽
GitHub - joshuay03/ractor-pool: A thread-safe, lock-free pool of Ractor workers with a coordinator pattern for distributing work
A thread-safe, lock-free pool of Ractor workers with a coordinator pattern for distributing work - joshuay03/ractor-pool
github.com
October 29, 2025 at 4:48 PM
Announcing RactorPool: github.com/joshuay03/ra...
Extracted from a project I'm building with Ractors. Currently requires Ruby 3.5 (3.5.0.dev). Goal is to have it stable for Ruby 4.0, when Ractors will be less experimental 🤞🏽
Extracted from a project I'm building with Ractors. Currently requires Ruby 3.5 (3.5.0.dev). Goal is to have it stable for Ruby 4.0, when Ractors will be less experimental 🤞🏽
I'm building something with Ractors and found a bug. Tried my best™️ to fix it: github.com/ruby/ruby/pu...
Side note: Might just be me, but as a non-frequent contributor, building ruby/ruby and running tests seems to be much more convenient and efficient than it was a couple years ago.
Side note: Might just be me, but as a non-frequent contributor, building ruby/ruby and running tests seems to be much more convenient and efficient than it was a couple years ago.
Fix segfault when moving nested objects between ractors during GC by joshuay03 · Pull Request #14947 · ruby/ruby
Fixes a segmentation fault when moving nested objects between ractors with GC stress enabled and YJIT.
The issue appears to be a timing problem in the ractor move process. When moving objects, move...
github.com
October 25, 2025 at 5:06 AM
I'm building something with Ractors and found a bug. Tried my best™️ to fix it: github.com/ruby/ruby/pu...
Side note: Might just be me, but as a non-frequent contributor, building ruby/ruby and running tests seems to be much more convenient and efficient than it was a couple years ago.
Side note: Might just be me, but as a non-frequent contributor, building ruby/ruby and running tests seems to be much more convenient and efficient than it was a couple years ago.
September flew by pretty quickly… I kicked it off by attending #RailsWorld!
www.linkedin.com/posts/joshua...
www.linkedin.com/posts/joshua...
#railsworld | 🍯 Joshua Young
Attended the third edition of Rails World earlier this month along with Jason and Julián, back in Amsterdam once again! A big thank you to Buildkite for sponsoring the three of us to attend this year....
www.linkedin.com
September 29, 2025 at 11:55 AM
September flew by pretty quickly… I kicked it off by attending #RailsWorld!
www.linkedin.com/posts/joshua...
www.linkedin.com/posts/joshua...
I’ve added support for distributed deployments: github.com/joshuay03/di...
Couple of ideas to follow up on:
- Profile dashboard
- Profile comparisons
Couple of ideas to follow up on:
- Profile dashboard
- Profile comparisons
September 22, 2025 at 10:05 AM
I’ve added support for distributed deployments: github.com/joshuay03/di...
Couple of ideas to follow up on:
- Profile dashboard
- Profile comparisons
Couple of ideas to follow up on:
- Profile dashboard
- Profile comparisons
Satisfying memory and CPU improvements after enabling Puma preloading + Process.warmup on one of Buildkite's services (our agent shard). Just rolled this out to all services - keen to see the broader impact!
August 30, 2025 at 8:36 AM
Satisfying memory and CPU improvements after enabling Puma preloading + Process.warmup on one of Buildkite's services (our agent shard). Just rolled this out to all services - keen to see the broader impact!
I wrote (or rewrote) some gems to get better at Ruby C extensions and learn about these topics (CAS and mmap):
- github.com/joshuay03/at...
- github.com/joshuay03/mm...
- github.com/joshuay03/at...
- github.com/joshuay03/mm...
July 26, 2025 at 4:24 AM
I wrote (or rewrote) some gems to get better at Ruby C extensions and learn about these topics (CAS and mmap):
- github.com/joshuay03/at...
- github.com/joshuay03/mm...
- github.com/joshuay03/at...
- github.com/joshuay03/mm...
I'm curious about this too. With YJIT in maintenance mode, bug fixes, UX improvements, etc., are probably welcome (a colleague recently found and fixed one). But with ZJIT being greenfield WIP, I'm not so sure. Completely understandable if that's the case though.
Is there any point hacking on ZJIT or YJIT if I’m not a Shopify employee?
#ruby
#ruby
June 13, 2025 at 10:08 PM
I'm curious about this too. With YJIT in maintenance mode, bug fixes, UX improvements, etc., are probably welcome (a colleague recently found and fixed one). But with ZJIT being greenfield WIP, I'm not so sure. Completely understandable if that's the case though.
Reposted by Joshua Young
#RubyKaigi late night with #RubyFriends !
April 16, 2025 at 4:23 PM
#RubyKaigi late night with #RubyFriends !
Announcing Dial, a Rails application profiler: github.com/joshuay03/dial
I've longed for a free tool that provides Datadog-like profiles, with accurate GVL and GC activity. Thanks to @jhawthorn.com's amazing work on Vernier, all I needed to do was integrate it with Rails and let it do its thing.
I've longed for a free tool that provides Datadog-like profiles, with accurate GVL and GC activity. Thanks to @jhawthorn.com's amazing work on Vernier, all I needed to do was integrate it with Rails and let it do its thing.
GitHub - joshuay03/dial: A modern profiler for your Rails application
A modern profiler for your Rails application. Contribute to joshuay03/dial development by creating an account on GitHub.
github.com
April 10, 2025 at 1:05 PM
Announcing Dial, a Rails application profiler: github.com/joshuay03/dial
I've longed for a free tool that provides Datadog-like profiles, with accurate GVL and GC activity. Thanks to @jhawthorn.com's amazing work on Vernier, all I needed to do was integrate it with Rails and let it do its thing.
I've longed for a free tool that provides Datadog-like profiles, with accurate GVL and GC activity. Thanks to @jhawthorn.com's amazing work on Vernier, all I needed to do was integrate it with Rails and let it do its thing.
Random thought about Ruby thread scheduling fairness that I don't have sufficient knowledge of the VM to answer myself—without probably banging my head against a wall for a couple of days or weeks 🧵
March 9, 2025 at 9:48 AM
Random thought about Ruby thread scheduling fairness that I don't have sufficient knowledge of the VM to answer myself—without probably banging my head against a wall for a couple of days or weeks 🧵
#24 of 564 contributors to Rails last year—not too shabby for mostly working on OSS in my free time! Hoping to keep the momentum going in 2025 🚀
contributors.rubyonrails.org/contributors...
contributors.rubyonrails.org/contributors...
Rails Contributors - Date Range
Ruby on Rails contributors
contributors.rubyonrails.org
January 1, 2025 at 10:50 PM
#24 of 564 contributors to Rails last year—not too shabby for mostly working on OSS in my free time! Hoping to keep the momentum going in 2025 🚀
contributors.rubyonrails.org/contributors...
contributors.rubyonrails.org/contributors...