JRuby 9.4.13.0 Released

Tuesday, June 10 2025

The JRuby community is pleased to announce the release of JRuby 9.4.13.0.

JRuby 9.4.13.x targets Ruby 3.1 compatibility.

Thank you to our contributors this release, you help keep JRuby moving forward!

Stability

  • Fixed a slow memory leak in subclass management. (#8842, #8844)
  • Fixed a potential deadlock during multi-threaded boot and concurrent JIT compilation. (#8845, #8849)

Usability

  • Backported JRuby .sh launcher features from JRuby 10, including AppCDS flags for improved startup time. (#8565, #8625, #8626, #8652, #8653, #8656, #8754)

56 Issues and PRs resolved for 9.4.13.0