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You can have a look at the JIRA release notes
Snapshots
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For those who want to test the very latest versions of Groovy and live on the bleeding edge, you can use our snapshot builds. As soon as a build succeeds on our continuous integration server for the Groovy 1.7, Groovy 1.8 and Groovy 1.9 branches, a snapshot is deployed to Codehaus' snapshot repository.
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