The Apache project managers removed the new parser from the Groovy 2.6 betas over 6 months ago after officially canceling it and saying Groovy 3 would be the next release. But no real work has been done on Groovy 3 since then. I'm guessing they really intend releasing version 2.6 some time in the future. Perhaps they'll say "Groovy 3 is still far off and Groovy needs another release, so let's resurrect Groovy 2.6". Don't expect to see Groovy 3 move beyond alpha version anytime soon.