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If you're looking for a longer-term project, we have a list of ideas for new projects for different levels skill and expertise. Alternatively you may look through the forums and mailing lists for suggestions for improvements. You may be able to find a mentor for your projects through illumos Students.
The OpenSolaris bug database also has a list of bugs for which patches are accepted. You can use the following list of bite-size bugs to find easy problems to tackle, but be sure to check if the bug in question is already fixed by checking its status, since that list was last updated in October 2009.
While the OpenSolaris bug database is no longer available, a third-party archive of the OpenSolaris bugs has a list of bite-size bugs which can help you find to find easy problems to tackle.
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