MariaDB has been accepted for Google Summer of Code 2017. This is a very important event for open source software in general and MariaDB in particular. We have many interesting project ideas. As a former GSoC student, I highly recommend any interested student to get involved. Ask us questions about the projects or propose alternatives to what we have already showed. All of these will help you better understand what we are aiming for and consequently improve your chances of getting a proposal accepted.
A brief description about some of the projects I personally would be interested in mentoring:
This project is relatively self contained, which should be good for a beginner to large code bases. The main idea is we want to get a better tool to run our tests. We also want to be able to write clearer, simpler and more stable tests. Improving the grammar of mysqltest will aid in that. The project's final goal is open ended. There are many potential ideas on what to implement or change. The trick here is figuring out (with your mentor ofcourse) which are worthwhile and which would take too long or not provide enough utility.
This is one of the most requested features from the community that we have on the list this year. Replication is a tricky business in MariaDB (and databases in general). We have a nice feature called GTID that allows for interesting replication setups. Understanding how GTIDs work is your first step into tackling this problem. Luckly there are a bunch of follow up links from the jira page where the whole approach is explained. I think this project is quite good as a stepping stone into replication. We have a nicely contained binary mysqlbinlog which helps DBAs and developers read and understand binary logs. We want this tool to support GTIDs. If you like a challenge and don't mind debugging one or two hexdumps from time to time, this could be a very rewarding experience.
Having said all this, I encourage all students to introduce themselves on irc (freenode #maria) and on the maria-developers mailing list. Beware of timezone differences and don't be discouraged if your IRC message is missed. The maria-developers mailing list is your best bet in getting your answers. We aim to reply to all emails.
The sooner you submit your draft proposal, the sooner we can offer feedback. You can then use that feedback to improve it and improve your chances of getting accepted. Also, check out my other post on GSoC from a mentor's perspective. This might give you a few more hints into how we approach the selection process. Good luck to anyone interested in applying!