The MariaDB Worklog is open to everyone at http://askmonty.org/worklog/index.pl (a free account on the developer wiki is required to suggest new tasks and add comments, votes, donations etc.). The account signup page for the wiki is here.
If you find something in the worklog that you really would like to have done, you can commit to donate some money to the developer when this is done. (Search after "Make offer" on the worklog item you would like to sponsor).
If there is something in worklog which you would like to develop, you can contact us at 'maria-developers (at) lists.launchpad.com' or 'community (at) askmonty.org'. If you deliver a working solutions that is accepted into the MariaDB source tree, you will get 60 % of the so far committed money. The rest of the money is kept by MariaDB Corporation Ab for help managing the project, code reviews, bug fixes, testing, maintenance, updates and merges to future MariaDB versions.
You can also add a link in the MariaDB worklog to tasks to the MySQL worklog. Just refer to the MySQL task as #WL<task number>
Source Code for Worklog
The source code for the Worklog application is hosted on Launchpad. The license is GPL.