Google Summer of Code (GSoC) 2023 ideas page

This is work in progress! New projects are being added as we confirm mentors.

NEW: Office Hours.

Each Sunday (depending on your timezone) we will hold office hours. You can show up and ask your questions. At least one org admin and/or mentor will be around, maybe more. No need to be formal, or even have the camera on if you're shy (but you can).

To connect, go to this google meet link.

Start date: 2023-01-29

Hours: Sundays at 8:30 AM PDT -7:00 hours (Pacific Daylight Time) which is 17:30 in Central Europe (until the clock changes there) and 9 PM in India.

(use San francisco Time for "official clock" - 8:30 AM in San Francisco is what matters, if you want to add your local time here send a pull request).

There's no agenda to these meetings. Someone from the team will be around, everyone is welcome, you can ask about GSoC, the org, your project, etc. If there's some other participants asking questions you can stay around and listen.

We will start at 8:30 and stay around for at least for 30 minutes, so you can show up at any time. At 9:00 if there's a conversation going on we will continue so it might last longer than 30 minutes (as long as needed).

Welcome to our ideas page. It's great you want to start early. Please join us in our slack channel! (we'll leave this as an exercise for you to find --- it's on our website).

As you will see, this year has a lot of Rust. The reason is simple: Security. Our C code base has known (and we suspect, a lot of unknown) security issues caused by the usual memory management in C. Lots of people have touched the code over the years, and it shows.

There's also Flutter, which we love, and more.

We will provide resources for students --- we'll give access to a high-speed server, all our samples (we'll even ship a portable drive with them anywhere in the world, so don't worry about slow connections) and various other perks.

You are welcome to check out the page (actual ideas at the bottom of the page, with each project having it's own separate page as well) and start early in the community bonding process as well as learning a bit about our code ethics and practices. And of course, we'd love you to stay around even if we are not invited to GSoC or if we cannot invite you as a student.

The ideas we currently have

Important: If you have something else in mind that relates to subtitles and accessibility please get in touch. We prefer that you do something that you are passionate about even if it's something we hadn't considered.

After you check out our ideas please continue reading to the bottom of the page to get information about who we are, how we collaborate, what resources we will provide to you, etc.

Some tasks descriptions are still vague. We know that. Feel free to get in touch for questions, or just check their page from time to time. We will update the descriptions often.

CCExtractor Rust rewrite

GSoC 2021 was quite successful on this front. The 708 decoder was rewritten in Rust, and in the process we fixed all the known (then) issues with 708. The student who did all this work (Punit Lodha) is going to mentor in 2022.

GSoC 2022 had partial success, with one of the projects (608) failing, and another one (HardSubX) succeeding.

In 2023 we'd like to tackle these tasks. If you're interested, you can get some feeling of the system by fixing

Or, to generally show that you know some Rust, tackle something from these very popular Rust projects (they're not related to us, even though we use them and we've committed code from time to time) and send us links to the PRs:

NameDescriptionTech you need to knowTech you will learnDifficultySize
Rewrite 608 decoder in RustCEA-608 is the American standard for analog subtitles. It also carries things like emergency alerts, basic TV guide, and content classification. We have a complete implementation in C that works OK (possibly with some bugs) but that is not really very well organized. We'd like to port it to rust. We will provide you with the official technical standards.(Some) Rust, Some (C)Analog subtitles, XDS Working with standards.Medium350 hours
Rewrite the OCR subsystem in Rust.We use tesseract to OCR bitmap based subtitles. It's a great library, but because its input is a bitmap that is preprocessed (so provide a reasonable input) there's lots of places in which there can be buffer overruns, underruns… many of the problems that Rust shines on are evidenced here. So a Rust rewrite of this would be a big win.OCR Rust FFITesseract Imaging OCRMedium350 hours

Support tools we and other orgs use as part of their development process

NameDescriptionTech you need to knowTech you will learnDifficultySize
The sample platform (/ continuous integration) projectThe sample platform is a good way to help new contributors to check if their code doesn't introduce any regressions. We want to squash the last bugs so it's fully usable for all our CCExtractor contributors, just as we intended to. This project is guaranteed to be selected if the proposal is good.Git PythonGoogle Cloud API's GitHub Actions GitHub API's Continuous Integration (CI) Automated deployments GitHub integrationEasy/Medium175 hours

Multimedia (misc)

NameDescriptionTech you need to knowTech you will learnDifficultySize
Upgrade FFmpegFFmpeg is the premier open source video library. We use it to decode video to be able to process burned-in subtitles. They recently made breaking changes to their API (worth it) and the clients need to be updated. CCExtractor is one such client.Some CVideo, subtitles, API integration, FFmpegEasy-Medium175 hours

Virtual Reality

NameDescriptionTech you need to knowTech you will learnDifficultySize
VirtualDesktopSome VR headsets such as Meta's Quest 2 come with a Virtual Desktop tool that lets you connect your computer to the headset and get virtual desktops. There's lots of YouTube videos on this topic, here's one. . There's a headset component and a computer component. The computer component exists for Windows and Mac, but not for Linux. That's what we want to build.A system language such as C, C++ or RustLinux desktop internals, VR internalsMedium-Hard350 hours


NameDescriptionTech you need to knowTech you will learnDifficultySize
ruTorrent mobile interface (II)ruTorrent is a popular web interface for rTorrent, which is possibly the most used BitTorrent client in linux. Last year we started a new project to write a Flutter based interface and was successful and it's gaining traction on its own. We want to work on that project and include new features.FlutterBitTorrentMediumDiscuss
support more torrent clientsWe'd like to add support for other clients to our ruTorrent mobile interface (which of course will get a new name): Flood and Deluge.FlutterAPI, TeamworkMediumDiscuss
Flood MobileThe project was a part of GSoC'21, GSoC'22 and currently have a version which interacts with the Flood backend. It have great features such as use magnet/torrent file to download a torrent, RSS feed, select torrent files to start downloads from any location in device for example: File Explorer, WhatApp etc, notification action support and many more. This year we would like to make app more stable by shifting the app to RiverPod/Bloc from Providers, improved testing, improve the notification support etc.FlutterUser Experience, Scalability & TestingMedium175 hours
NetioRecently it was announced that dio which was greatly used by developers as a powerful HTTP client for Dart/Flutter will not be maintained further. This year we would like to develop our own HTTP client package to support our existing applications and avoid dependency on other packages. This would be also a potential contribution to the flutter community.Flutter and DartScalabilityMedium-Hard350 hours
BeaconThis project was started in 2021 and it got a great push also during 2022. It aims to ease the group travelling (or hiking). By using this, the group leader would be able to share his live location with the entire crew. We want to improve on past work, include new features, and release it. Note: This project has really gotten traction and there are a lot of contributors working on it now.FlutterScalabilityMedium175 hours
TaskWarriorTaskwarrior is a very nice command-line tool (yes, in 2022 — and I love it!) to manage task list. This year our target is to making our own Taskserver(or finding alternative to freeinc). And also a functionality to make our own Taskserver like we do in CLI. We want to improve on past work, include new features.FlutterScalabilityMedium175 hours
It's UrgentA notification tool that lets the sender decide if what he/she has to say is so important as to interrupt the receiverFlutterScalabilityMedium350 hours
Ultimate Alarm ClockThe ultimate alarm clock, with features no other one has. And free!FlutterGood application designMedium350 hours


NameDescriptionTech you need to knowTech you will learnDifficultySize
URL shortener, with a twistA URL shortener converts a long URL into a shorter one. There are many use cases. Some times it's just the shortening itself we want, for example to share it on twitter. Other times it's about obfuscation. We want to create our own, but with some unique features.Any language you wantInternet infrastructureMedium175 hours
Add complex layouts to swaySway is a drop-in replacement for i3, a popular windows manager for Linux that finally gets rid of the ancient X11 protocol. It's fantastic, but it's still missing support for complex scenarios. We'd like you to work on that support.CSwayHard350 hours


We use jesec/rtorrent. It provides a more modern base with Bazel/CMake and C++ 17 (instead of autotools and C++ 0x). Plus, your works are guaranteed to be incorporated if they match expectations.

Note - we want to have a unified rtorrent that gets the best from jesec's and novik's work. See the first project in this section.

NameDescriptionTech you need to knowTech you will learnDifficultySize
Unify flood and ruTorrent's rtorrent versionsEach of the two most important rTorrent frontends have their own backend version. We need to create a version that works with both ruTorrent and Flood.C++Mostly Docker and rTorrent internalsEasy-Medium350 hours
a modern RPC interfacerTorrent currently uses an antique XMLRPC interface, which is limited in capability, not scalable, hard to use, insecure and low-performance. Community needs a modern RPC interface with full bidirectional, stream processing, incremental data loading and high concurrency capabilities, which allows real-time events for RPC users, reduced serialization/transfer overheads, potentially better security (with authentication and/or TLS), etc.C++RPC, Event LoopMedium/Hard350 hours
asynchronous name resolutionUDP tracker name resolution is not asynchronous at the moment, which causes blocking in the main thread and can block (timeout) other ongoing/incoming connections/transfers. c-ares or libwebsockets implementation is preferred, as c-ares is already used by curl, which rTorrent depends on, while libwebsockets may be used by a future WebSockets RPC interface.C, C++Threading, Event LoopMedium350 hours
improve scalabilityrTorrent has a well-defined threading behaviour, which makes it stable and light on resources. There are 3 permanent threads only: main, disk and scgi. However, in the age of Gigabit/10G connections, 3 threads are often not sufficient. Implement a new threading model with better scalability.C++ThreadingHard350 hours
scheduling/queuingIn some cases, users might want to download a series of torrents one-by-one without having to manually start the next when the previous is completed. Implement a scheduler along with a queue to allow users to limit the number of maximum simultaneous downloads. Enqueue if the user adds a download or decrease the limit. Dequeue when a download is completed or the user increases the limit. Keep the queue state across reboots.C++SchedulingMedium350 hours

New things we're currently interested on

NameDescriptionTech you need to knowTech you will learnDifficultySize
Mouseless for Linux v2 - i3 editionMouseless is a nice tool to practice keyboard shortcuts for a few popular apps. Unfortunately it's only available for Mac. Last year we created an open source one that runs on Linux. Using that work or not (this is your choice) we want to create one that helps use i3vm (the fantastic windows manager) using keys only.Your choice??Unknown175 hours

Niche ideas

We've moved the less mainstream ideas to their own page These ideas are not let important, but because they are somewhat esoteric we've decided to give them a place of their own :-)

About us

We are a small org, which means that your contribution will have a large impact. It's not going to mean a 0.5% improvement on a big project --- it's going to be more than 10% on a medium size one. If you like challenges and want a chance to shine this is your place.

We have we think statistically amazing continuity in the team: Most GSoC students from all the past years are still involved, even if they are no longer eligible as students. They still contribute code, and they mentor both in GSoC and the sister program GCI. As mentors, they also come to the Summer of Code summit which traditionally takes place in October.

We have mentors all over the world (North America, Europe, Asia and Australia), so time zones are never a problem. Our main channel of communication is a Slack channel to which everyone is welcome. We expect all accepted students to be available on Slack very often, even if you don't need to talk to your mentor. This will help you ask questions when necessary, and you might be able to help others out as well while working on your project.

Exception: If your country (such as Russia) has banned Slack please get in touch in we'll work out a solution with you. We absolutely want you to participate.

A mailing list is also available for those that prefer email over Slack. Note that getting replies might be faster on Slack though.

All our top committers will be mentoring. Many of them are former GSoC students or winners of GCI.


All accepted students get a programming book immediately after being accepted, with the hope that they read them before the coding starts. We want to see if this increases the quality of the work. So far we have selected these three books (pick one), but we're open to suggestions: Clean Code, Elements of Programming Interviews in Python, Cracking the code interview.

We will also provide to all accepted students: - 6 months of access (from the acceptance date) to all courses in - 12 months of access (from the acceptance date) to backtobackswe, which is a fantastic resource to learn algorithms, prepare for coding interviews, and in general learn fundamentals.

About what we use

This is what we use today. It doesn't mean this is what we want to continue using. Probably not --- we're really open to change. We're just describing the status quo so you know what you are getting into :-)

The core tool that names the organization (CCExtractor) is a command-line program written in C (not C++), and new core parts are being written in Rust.

The current GUI is written in flutter.

The testing tool we use to run regression tests is mainly written in Python, but it also used Javascript, CSS and some shell scripting. The Test suite is written in C#. One of the projects this year is to move it from a dedicated server to GSoC and improving the scalability of test runs.

The prototype real time subtitle website is written in NodeJS.

We also have a number of support tools that do a number of different things, from downloading subtitles from streaming services to translating them with Google Translate or DeepL. Most of them are written in Python, but since they are small tools that do their job you don't need to worry much about them.

For totally new things you can use whatever tool you feel is best for the job.

About sample media and other resources

We work with huge files. Not all of them are huge, but many are. We know that many students don't have access to high speed internet. To those students we will ship (as soon as they are selected) a portable hard drive with all our samples. So if your internet connection is not good, don't worry --- as long as you can plug a USB drive to your development computer you can participate with us.

We also have a shared Linux development server with lots of storage and a Gigabit uplink. Students get an account on it and they are welcome to use it. There's nothing there except our own work, so it's a trusted environment (for a server that is connected to internet of course).

The sample platform also hosts a bunch of samples, both which are small or decently sized.

Some projects have specific requirements, and we'll make sure that you get the resources you need: i.e. if your project requires some cloud resources (Google Compute Engine, for example), we'll make sure you get access to the resources.

In general, you are not expected to pay for anything (other than your own development computer and internet, of course) related to any project.

If you need anything not mentioned (such as a book) let us know. Within reason, we'll help you.

About the projects and getting accepted

Qualification: Our selection system is based on several factors. Of course no student ranks in all criteria, so don't worry when you read the list below.

Work on our core tool: Even if you are going to be working on something totally different. This might seen counter intuitive, but the thing is if you prove you can dig into our (messy) code base, find yourself your way around it, and fix a few bugs, you are just the kind of person we can trust to "figure things out". GSoC is among other things, a learning experience. No matter what project you decide to work on, there's going to be roadblocks, things you don't know how to do, etc. So we really like it when students embrace those situations.

Qualification tasks specific to the project: The detail page for some projects contains specific qualification tasks that apply to them.

Contributions to existing open source projects: This can be anything. From a good GitHub profile to pull-requests sent to any other existing project, participation in hackathons, Google Code-In, past GSoCs and so on.

A good proposal: This is the one criteria that is non-negotiable. Your proposal has to be good, period.

Project popularity: Some ideas just have more competition, so if participating in GSoC is a top priority for you (over working on a specific project), consider applying to one of the "niche" ideas. After all, that's a great way to get your foot in the door :-)

Best core tool tasks

We're added a difficulty level to most of our open issues on GitHub. Best thing you can do is head there and see if you are able to fix some of the easy ones and work your way up. We don't expect you to be able to do the hard ones but we'd be impressed if you did :-)

For some of the easy ones you don't even need to know C. Just being able to compile CCExtractor and dig around a bit will be enough.

The sample platform's issues are tagged with "gsoc-proposal-task", so you can easily see what you can work on.

Take home qualification tasks

If instead of working on existing code you'd prefer to show us your skills working on something new, you can pick one of these projects.

Community etiquette

It goes without saying that everyone in the community has to be polite and respectful, and consider everyone else a member of a team and not a competitor.

All developers are part of the team, by the way. Our Slack channel has mentors, code-in participants, other students, or developers and users that are none of the above but they all play some kind of role in CCExtractor's community.

Part of being respectful is giving consideration to everyone else's time. Most of us have day jobs, and as such are limited in the time we can use to guide you. We'd like to spend it on quality discussions, and not on things that are for example written on this website, things that you can easily retrieve by reading documentation on used libraries or on the software's help screen. Asking this kind of questions in the Slack channel shows little respect for our time. This doesn't mean you can't ask questions, but remember that being a clueless user and a lazy developer are two very different things. If you ask those questions you will probably get an answer as if you were a clueless user (polite no matter what), but if you apply to GSoC you will be considered a lazy developer. Google is your friend ;)

Tell things as you see them. Politely -you're not Linus-, but don't sugar-coat it. We know some parts of our code is poorly written, poorly documented, etc. It stands out, so you will know when you dig in. No one is going to be offended by having that code rewritten or refactored. Peer review applies to everybody's work and is done by everybody.

Cross project proposals

Because we use a number of libraries and in fact "are a library" ourselves (meaning other programs can link CCExtractor as a library, or invoke the binary) we interact with other communities and their software. From time to time there's a chance to do something interesting that affects CCExtractor and something else (FFmpeg comes to mind, but also Kodi, VLC, libGPAC, Red Hen, to mention just a few of our friends that typically participate in Summer of Code). So how does this work? As long as the work benefits CCExtractor and it's part of your summer project, we're OK with you spending some time on the other project. For example if you are improving our MP4 support, for which we use libGPAC, and need to fix or improve something on libGPAC you are welcome to do so. If you do, make sure you submit your changes to their maintainers and follow through with their merge process.

Your proposal

You can propose to do any of the following ideas, or you can bring your own. In any case, make sure you run them by us before you actually submit your proposal.

At the very least your proposal needs to:

  • Explain what you want to do, why it is important to you (don't make up a story here — the reason can be that you need it, that you just think it's cool, that you have an itch to work on it, etc), and why it could be important or useful to us.
  • Explain how you intend to accomplish the goal, in enough detail that makes it clear that you have done your homework. For example, “I will modify the CCExtractor binary so that it's able to convert audio to text with perfect accuracy” is the same thing as sending your proposal to the trash. You need to have a plan.
  • Detail the timeline explaining what the expected progress is for each week or every two weeks (pay special attention to the milestones within the GSoC timeline itself, of course) and how we should validate the results.
  • Detail what kind of support you will need from us. For example, if you are going to need test streams, hardware, access to a server, etc, let us know, so we can prepare everything for you as soon as possible.
  • Detail your expected working hours in UTC. We're used to weird working schedules, so don't worry about working in the middle of the night, or weekends instead of other days, etc. Knowing your hours may help us to match you better with a mentor.
  • Mention your planned absences. We don't need you to detail what you will be doing when you are not working of course, but if you are going away for any reason we need to know so we don't think you've abandoned.
  • Link to your GitHub (or any other repository) profile, if you have one, so we can take a look at your previous work.
  • GSoC is a coding program: This means that ideas that are about testing (unless it involves coding something to test our programs ;) ), website design, etc, are out.
  • However, we want to have good documentation: Make sure you have time to write a good technical article explaining your work.
  • Be realistic and honest with the timeline. Consider each week you should work around 30 hours. If your timeline reserves a lot of time for minor things we'll think that you are not going to be working full-time in GSoC. On the other hand if you promise to do things in a lot less than that it seems realistic to us it will seem that you don't really know how much work things take.
  • If you are going to be using 3rd party libraries (that's OK), make sure to validate that their license is compatible with GPLv2 (which is ours). List the libraries in your proposal. Check that they are cross-platform. If you will need to extend those libraries in any way please explain. In this case, your proposal should include time to get that extension submitted to the maintainers (we love to contribute to other projects).

Something else: Mentors often have their fingers in several pies. If you send the same proposal to several orgs everyone will know. So do yourself a favor and don't do that. You can apply to several organizations and that's totally fine, but each organization will want to see that you have put the time to write a great proposal that is focused on them.

Useful resources

A great resource for GSoC.