Standard Library

• The non-gem standard library is upgraded to Ruby 3.4.5 #8967
• rexml is updated to 3.4.4 to address CVE-2025-58767. #9011
• syslog is moved to a default gem at version 0.4.0. The syslog gem now includes JRuby support. #9109, ruby/syslog#1
• strscan is updated to 3.1.7. #9159

Documentation

• Ruby ri documentation for core and standard library are now included in the release distribution. #9049, #9052

All Issues/PRs

• #8707 WARNING: A terminally deprecated method in sun.misc.Unsafe has been called
• #8727 Cannot install latest rubocop
• #8730 Launcher: Defensive fixes
• #8758 Require is not working for .class file if the class is inside a module since 9.3.0
• #8810 Possible fix for 8809
• #8923 NameError for autoloaded constant with private_constant
• #8934 JRuby under Java 22+ always thinks it's running under a TTY
• #8940 Verify to_s is string or fall back on anyToString
• #8947 New check for System.console tty on JDK 22+
• #8955 Range#count always returns size for Integer bounds
• #8956 Handle argument or block passed to Range#count
• #8958 Concurrent requires can lead to StringIndexOutOfBoundsException
• #8960 Fix index -1 error while searching for feature path
• #8962 Upgrade polyglot and remove openssl lib hack
• #8967 Update stdlib to 3.4.5 and clean up old files
• #8975 Use RuboCop to clean up poms (10.x)
• #8976 Regression in keyword argument matching in JRuby v10.0.1.0
• #8978 Additional fixes for scheme-based globbing
• #8984 glob refactoring
• #8985 Fix language spec where error string changed
• #8987 InvokeDynamicSupport.findVirtual fails with IllegalAccessException: symbolic reference class is not accessible
• #8989 Explicitly request access before Lookup.find*
• #8994 autoload + private_constant do not play well together
• #8995 private_constant should just update existing autoload
• #8996 Avoid binding unreadable modules' classes
• #8998 Time#localtime incorrectly treats zero offset as UTC (regression in v10.0.2.0)
• #9006 Consider .class a source extension during search
• #9007 Handle warn(foo, uplevel: nil)
• #9009 Encoding a string with undefined chars fails with NoMethodError
• #9010 Fix "+00:00" and 0 being treated as UTC by Time#localtime and Time.at
• #9011 Update rexml gem to solve CVE-2025-58767
• #9016 [fix] regression calling static hash() method on Java proxy
• #9017 can not use Java class with static hash() method
• #9018 Parser does not convert newlines reading \r\n on Windows
• #9019 We need to remove \r from heredoc strings
• #9021 Retire safe double processing utilities
• #9024 Move all main classes to org.jruby.main package
• #9027 Add "since" to bare Deprecated annotations
• #9035 IO#read does not clear code-range for buffer argument
• #9036 fix: clear code-range when re-using a string buffer
• #9038 Add opens and native access to all jar manifests
• #9039 Update all jnr dependencies
• #9041 Migrate .java-version contents to .jruby.release
• #9049 ri docs are not available for core
• #9050 Marshal fails to load an encoding with an encoding ivar
• #9051 Ignore encoding when unmarshaling an Encoding
• #9052 Download and include in dist CRuby's rdoc data
• #9058 Implement efficient unshifting
• #9059 Reserve extra space before elements when unshifting
• #9063 Hash's compare_by_identity state does not marshal
• #9065 Preserve compare_by_identity for marshaled Hash
• #9068 Windows CI spec runs
• #9073 fix: Permit overriding of JSA file location using ENV variable
• #9084 object_id improvements
• #9094 Implement GC.config [Ruby 3.4]
• #9097 Update jruby-openssl to v0.15.5 to resolve BouncyCastle 1.79 vulnerability (sonatype-2025-001911).
• #9098 Fix CoverageData.mergeLines when coverage increases
• #9101 Cached fixnums for immediate values
• #9103 Update jruby-openssl to 0.15.5
• #9106 Use smaller default size for many collections
• #9107 Separate Java version out of rbconfig 'arch'
• #9108 Tidy up default gems
• #9109 Switch to syslog gem
• #9110 Calling inspect on proc resets line in source_location
• #9112 Prevent modifying state in RubyProc
• #9117 Add file path to error message when unlinking non-existing file
• #9122 Unexpected jruby.sh error messages on Windows
• #9127 fix(launcher): correct parsing of java release files under Bash/msys2 etc on Windows
• #9138 Copy Data type's var table manager with new realClass
• #9141 refactorings and cleanup motivated by error-prone
• #9142 Change GC's methods from module_function to metaclass methods
• #9145 Never trust external content for FString
• #9152 Marshal.dump corruption for large Array structures
• #9157 bump included gems
• #9158 Use same key match for containsKey
• #9159 Update strscan to 3.1.7
• #9182 Fix NoMethodError when encoding with invalid: :replace option
• #9188 Different arguments for each.map vs each and map alone (10.0)
• #9189 Fixes #8952. Nest it should be different its
• #9190 Backport implicit local variable fixes from 10.1
• #9191 Fixes #8952. Nested 'it' behavior broken
• #9192 Stab at Fixing #8976
• #9194 BigDecimal#+, #-, #add, #sub always try to cast result of coercion to RubyBigDecimal
• #9196 require "bigdecimal" does not install BigDecimal() if it was called previously
• #9199 Output formatting differences between jRuby 10.0.0.1 and Ruby 3.4 when converting Float to JSON
• #9200 Extract float formatting into a static method to use with to_json
• #9203 Invalidate method caches from generated populators
• #9204 Fix BigDecimal#+, #-, #add, #sub failing when coercing doesn't return a BigDecimal
• #9205 Fix encoding fallback error handling and error message formatting