table of contents

Thoughts on Appyling to Google Summer of Code

Over the past few years I’ve been involved in Google Summer of Code (GSoC), a program that sponsors students to write code for open-source projects, as part of Mozilla. I’ve been both a mentor and administrator, Florian Quèze and I frequently get asked questions about what students should do to apply to GSoC. This post aims to give some resources and answers to those questions. (I should note that each open-source organization is different and this is based on my experiences at Mozilla. Your mileage may vary.)

Remember that none of this is meant as a guarantee for acceptance, it is just a few things that can help get you ready and improve your chances!

If you haven’t heard yet, then Mozilla has been accepted into Google Summer of Code (GSoC) 2016, this will be our 10th time participating in GSoC mentoring Organizations. Overally, the best way to prepare yourself for applying to GSoC is to get involved with the community you would like to work with. Some particular resources to help you in applying to GSoC are:

  1. Go read the Google Summer of Code website. Every part of it. Particular pages to point out are the:
    • Student Guide: Written by a variety of people in the GSoC community, it covers topics from contacting an organization, to applying, to not being accepted.
    • FAQ: If you still have questions after reading the above (or whenever you have a question), check here for answers before asking anyone. (In particular this includes questions about how to apply.)
    • The final important page to internalize is the schedule. It is a student’s responsibility to meet each of the deadlines.
  2. Mozilla has some good application advice on the idea page. I’ve included/expanded on this below:
    • Talk to the mentor. Contact them on IRC/e-mail/Slack/whatever that project uses. If you have trouble contacting a mentor, contact the organization administrators.
    • Read How Not To Apply For Summer Of Code and avoid doing the things listed there.
    • Read our examples of good applications: 1 2 3
    • It is entirely acceptable to apply for 2 or 3 projects, if more than one catches your eye; if the applications are high quality, that can improve your chances. However, more than 3 seems like spam.
    • Note that if a project suggests it would be helpful to know a technology you don’t know (e.g. XUL), you may be able to get away with learning on the job. Don’t be put off from applying if the project otherwise looks right for you.

Picking an Organization

Pick an organization you’re truly interested in helping. I really can’t stress this enough. “Truly interested in helping” might mean many things:

  • You believe in an organization on a philosophical ground.
  • You use the program/library/service/etc. that the organization produces.
  • …many other things…

Throughout this post I use “organization” and “community” synonymously, but organizations likely have smaller communities within them, each with their own culture, beliefs, etc. Even within a small community, members will not share all the same opinions!

A pet peeve of mine is that a student should use (or at the very least try) the product the community makes. It is difficult (if not impossible) to understand the needs and wants of a community without utilizing what they’ve poured their time and energy into.


Different communities interact in different ways (and frequently a single community interacts in multiple ways). Common ways include:

  • Instant messaging (IRC, XMPP, Slack, hipChat, etc.) for day-to-day chatter, help, and off-topic banter.
  • E-mail / mailing lists / newsgroups for project wide discussion, announcements, etc.
  • Bug trackers (Bugzilla, GitHub, Trac) for technical discussion and reviewing code.

Choose whichever way of introducting yourself that you’re comfortable with. It can be useful to “idle” before introducing yourself (i.e. watch how a community interacts).

This can be important to figuring out a communities culture, e.g. how friendly is the community to new-comers? Are they open to helping or do they just expect patches to be submitted? Remember that it’s important for you to feel comfortable with a community, you’ll be spending a significant amount of time interacting with them!

If none of the above seem appropriate, or you’re unsure, contact the organization administrator directly. I’d suggest asking pointed questions, as an organization administrator is much more likely to respond quickly in that case.

Getting Accepted

We’re frequently asked how a student can improve their chances of getting accepted by an organization. GSoC is a very self-driven program, especially if your mentor is a volunteer. Being a self starter can be a boon for being accepted.

  • Find a project you’re interested in doing and talk to the mentor / community responsible.
  • Ensure you have a development environment set-up (for example, make sure you can build Firefox, understand what needs to be done after making changes, etc.).
  • Figure out where resources are for the project (i.e. Where are technical discussions? Where can you find documentation?)
  • Find minor bugs related to the project you’re interested in and work on fixing them. (This might be more difficult if your project would add an entirely new piece of code!)
  • Get used to the way the community works and functions.

Building an Application

The above should help feed into your application. In particular, it should help to build a realistic schedule for your application. (Scheduling is difficult even for seasoned engineers, but the above work should help make a more accurate schedule.)

  • Develop a plan for splitting your work into discrete chunks that can be merged separately. Smaller changes are easier to review, can (generally) land faster, and are easier to test. Of course, each project is different, but work with your (potential) mentor.
  • Estimate the amount of work each part of the project will take (you’ll have some experience in the code base already, leverage that).
  • Estimate how long reviews will take. (All code at Mozilla must go through a review process before it is merged into a product. You might even need multiple reviewers if your code touches many different parts of a codebase! Different people review code on different schedules, etc.)
  • Understand how quickly your changes would be merged and released. (How quickly will your code hit a larger audience?)
  • Understand the pieces besides code that you might be asked to do. Will you need to add/update documentation? Add new tests? Keep an old API intact?


This is just a few ideas of what I look for when reviewing a Google Summer of Code application. To repeat, try to understand an organization’s members, get involved and gain experience, try to build an accurate schedule. An additional thing I’d like to add is to respect your mentors time, especially for GSoC, many mentors are volunteers! You’ll likely be working on their project more than they do during GSoC!

Please let me know if you have any additions or comments! If you have specific questions that pertain to your application at Mozilla, please contact me individually.