Ruby 4.0 changes - Ruby Changes

This changelog is created as a gift to the Ruby community by a serving Ukrainian officer during the full-scale Russian invasion of Ukraine. If you find my work useful, please donate to the Ukrainian cause. This page lists many trusted grassroots fundraisers, both military and humanitarian. Note: As already explained in Introduction, this site is dedicated to changes in the language, not the implementation, therefore the list below lacks mentions of lots of important CRuby implementation updates, that continue to be steadily delivered by the core team. One (but not the only) notable is introduction of a new experimental JIT compiler named ZJIT.