All Couchbase SDKs are Open Source, and most source is Apache 2.0 licensed (there's a little bit of MIT license in there too). A number of people have stepped forward with new features and fixes, and we hope you will too. This should help you get started.

Issue Tracker, Source Code & Code Review

Java

Issues: http://www.couchbase.com/issues/browse/JCBC
Source: https://github.com/couchbase/couchbase-java-client
Code Review: http://review.couchbase.org/#/q/project:couchbase-java-client,n,z

.NET

Issues: http://www.couchbase.com/issues/browse/NCBC
Source: https://github.com/couchbase/couchbase-net-client
Code Review: http://review.couchbase.org/#/q/project:couchbase-net-client,n,z

PHP

Issues: http://www.couchbase.com/issues/browse/PCBC
Source: https://github.com/couchbase/php-ext-couchbase
Code Review: http://review.couchbase.org/#/q/project:php-ext-couchbase,n,z

Ruby

Issues: http://www.couchbase.com/issues/browse/RCBC
Source: https://github.com/couchbase/couchbase-ruby-client
Code Review: http://review.couchbase.org/#/q/project:couchbase-ruby-client,n,z

C/C++ (libcouchbase)

Issues: http://www.couchbase.com/issues/browse/CCBC
Source: https://github.com/couchbase/libcouchbase
Code Review: http://review.couchbase.org/#/q/project:libcouchbase,n,z

Python

Issues: http://www.couchbase.com/issues/browse/PYCBC
Source: https://github.com/couchbase/couchbase-python-client
Code Review: http://review.couchbase.org/#/q/project:couchbase-python-client,n,z

How to Contribute

As with all Open Source, there are many, many ways to contribute. Soome of these don't even involve submitting code.