|Jalview is open source, and primarily written in Java. The Jalview Release History lists all of the previous versions and links to their release notes, and if you want to use an earlier Jalview version, take a look at the Jalview Version Archive.|
If you want to report a bug, sugest a new feature, or generally help make Jalview better, then please take a look at the Jalview JIRA bugtracker.
If you're a developer, you'll also want to browse the Jalview GITweb, which provides a view of the Jalview GIT repo at http://source.jalview.org/git/jalview.git
If you want to contribute code to Jalview, then sign up at our issue tracker, and send an email the Jalview coordinator (Jim Procter) to be made a developer on the Jalview project. If you want to add new calculation services to the Jalview desktop, then you might also be interested in working on Jalview's sister project, JABAWS.
We are happy to help out if you want to use Jalview for your own research project, and if you are in full time education, keep an eye out for the Phyloinformatics Summer of Code, which is a way for students who want to work on Jalview to be supported by the Google Summer of Code.