This is the fork of beanshell.org called Beanshell2 which lived between 2011 and 2014 at code.google.com. The motivation of the fork was that the original author was no longer maintaining it.
In 2015 the repository moved here when Google retired their code hosting site.
The old version is again maintained at github.com/beanshell. There is some ongoing effort to integrate the changes and improvements made to the project there.
The development branch here is v2.1, the latest 'released' version is 2.1.9 which maps to commit a70056fbe9727d8eadf8e21f3089cbe9f4f0913e.
See releases page for more information.
For contributing: Please post your pull requests against branch v2.1. There is an ongoing effort to change the licence to Apache License, version 2.0 (see also issue #110), so all contributions will be dual licenced.