Mainstreaming RakuAST
Yes, it looks like the next release of Rakudo (2026.09, tentatively planned for 26 September) will be the first Rakudo release that will use the new Raku backend (based on a new grammar producing RakuAST) as the default when compiling a writting in the Raku Programming Language . Until then one had to specify the RAKUDO_RAKUAST=1 environment variable to activate the new backend. It is a major step towards releasing the next Raku language level, tentatively still called "6.e" for historical reasons, later this year. Note that the 2026.09 Rakudo release will not remove the old backend from the core just yet: you will be able to activate the old backend by specifying the RAKUDO_LEGACY=1 environment variable. However, the old backend will be removed when the 6.e Raku language level is released. So it is very important to check what these changes will mean for you! Immediate effects So what will a user of this Rakudo release notice with their apps and libraries? Nothing In the past weeks the Raku ecosystem has been thoroughly scoured for code that would stop functioning in RakuAST. Some finds turned out to be omissions / errors in the RakuAST implementation (which then have been fixed). Others turned out to be modules doing (semi-)naughty things, for which Pull Requests were made to ensure they will continue to operate in RakuAST. Running slower It could well be that your code is running without issues, but all of a sudden runs slower than before. Years of optimizing the old backend were mostly lost in RakuAST. And had to be re-created in the RakuAST-based backend. Which may have lost a few nooks and crannies that affect the execution speed of your code. Slower execution should be reported as a bug, so that it can be fixed! Running faster One of the goals of the RakuAST projects was to be able to provide better optmizations. Some of the ideas for these optimizations have already been implemented in RakuAST. And as a part of this work, a lot of aspects of the runtime have