If you haven't upgraded yet, Ruby 4.0's garbage collection is generally much faster than 3.4. This patch release fixes the one area there had previously been a notable regression (allocating/freeing Classes).
@k0kubun.com talked about ZJIT, the next generation of YJIT for Ruby 3.5. He explained how to use it to improve Ruby’s speed in Ruby and Rails infrastructures.
We released Ruby 4.0.5 and published security advisory for CVE-2026-46727.
If you use Ruby 4.0.0~4.0.4, we recommend updating your Ruby version to 4.0.5.
www.ruby-lang.org/en/news/2026...
Ruby 4.0.2 Released www.ruby-lang.org/en/news/2026...
This is a routine update that includes a bugfix in YJIT for NoMethodError on Puma. We recommend upgrading your Ruby version at your earliest convenience.
Ruby 3.4.8 Released www.ruby-lang.org/en/news/2025...
This is a routine update that includes bug fixes. We recommend upgrading your Ruby version at your earliest convenience.
Ruby 4.0.1 Released www.ruby-lang.org/en/news/2026...
This release includes a bugfix for Kernel#sleep, along with other bugfixes. We recommend upgrading your Ruby version at your earliest convenience.
Ruby 4.0.4 Released www.ruby-lang.org/en/news/2026...
This is a routine update that includes bugfixes. We recommend upgrading your Ruby version at your earliest convenience.
Ruby 4.0.3 has been released. It updates ERB to 6.0.1.1 for CVE-2026-41316.
If your application calls Marshal.load on untrusted data AND has both erb and activesupport loaded, please update your ERB version. You may update Ruby to 4.0.3 to do so.
www.ruby-lang.org/en/news/2026...
Ruby 4.0.4 Released www.ruby-lang.org/en/news/2026...
This is a routine update that includes bugfixes. We recommend upgrading your Ruby version at your earliest convenience.
