4.0 open about 9 months late (12/25/2025) 91% 23 issues (21 closed — 2 open) Related issues Feature #19057: Hide implementation of `rb_io_t`. Actions Feature #21221: Proposal to upstream ZJIT Actions Feature #21262: Proposal: `Ractor::Port` Actions Feature #21268: Implement a lock-free hash set for fstring table Actions Feature #21275: Update to Unicode 17.0 Actions Feature #21311: Namespace on read (revised) Actions Feature #21550: Ractor.shareable_proc/shareable_lambda to make sharable Proc object Actions Feature #21557: Ractor.shareable_proc to make sharable Proc objects, safely and flexibly Actions Feature #21701: Enumerator.produce accepts an optional `size` keyword argument Actions
4.1 open Due in about 3 months (12/25/2026) 70% 30 issues (21 closed — 9 open) Related issues Feature #8948: Frozen regex Actions Feature #21005: Update the source location method to include line start/stop and column start/stop details Actions Feature #21768: Remove deprecated functions Actions Feature #21788: Promote Thread::Monitor to a core class Actions Feature #21821: Add Stack and SizedStack classes Actions Feature #21881: Split the root box into the (newer) root box and the master of copied user boxes Actions Feature #21998: Add {Method,UnboundMethod,Proc}#source_range Actions Feature #22010: Update to Unicode 18.0 Actions Feature #22081: Core type definition migration from `ruby/rbs` to `ruby/ruby` Actions Feature #22212: Add Thread::Backtrace::Location#source_range Actions Feature #22226: Ractor: class/module ownership -- restrict modification to the Ractor that created it Actions Feature #22277: Make `rb_gc_register_address` Ractor-local Actions Feature #22300: `Ractor.check_isolation`: report Ractor isolation violations as warnings instead of raising Actions Feature #22329: Specify --disable-gem per Ruby Box Actions