GSoC 2026: Development of a new Calibre plugin for BookBrainz

Hello, Everyone!

I am Md Waqib Sk (waqib2992 on IRC), an undergraduate student at Indian Institute of Technology Kharagpur. This summer, I had the opportunity to participate in Google Summer of Code 2026 with MetaBrainz, where I worked on developing a calibre plugin for BookBrainz.

I was mentored by Nicolas Pelletier (monkey on IRC). This post summarizes my project, its outcomes, and my experience over the course of the program.

Project Overview

Calibre is a free, open-source e-book manager used to organize and read digital books. My project was about introducing a new plugin that connected calibre with BookBrainz.

The main proposed features of the plugin were:

1. Metadata update: Search selected book from calibre in BookBrainz database and update it’s metadata accordingly.

2. Browse BookBrainz: Search editions/public collections by name/bbid through the plugin and add or download the corresponding metadata.

Plugin Repository: https://github.com/bookbrainz/CaliBBre

GSoC 2026: Bringing Internationalization (i18n) to BookBrainz

Introduction

Greetings, everyone!

I am Garv Thakre (@garvthakre:matrix.org on Matrix), an Agentic-AI FullStack Developer . This summer, I had the opportunity to participate in Google Summer of Code 2026 with MetaBrainz, where I worked on the internationalization (i18n) for BookBrainz.

I was mentored by Nicolas Pelletier (@monkey:chatbrainz.org on Matrix). This post summarizes my project, its outcomes, and my experience over the course of the program.

Project Overview

BookBrainz aims to collect information about every book ever written, but until now, the interface was only in English. Since books exist in thousands of languages, having an English-only UI made it tough for non-English contributors to navigate, read, or add metadata.

My main goal this summer was to get BookBrainz ready for translation and set up the foundation so the community can actually start localizing it. Here is what that involved:

GSoC 2026: Compose Multiplatform Migration of ListenBrainz-Android

Hi everyone,

I’m Nirvan Jain (nirvan_jain on IRC, nirvan73 on GitHub), I’m currently a pre-final year student at IIIT Jabalpur. This summer I was offered this opportunity to work with MetaBrainz through Google Summer of Code on migrating the ListenBrainz android app to Kotlin Multiplatform and Compose Multiplatform, so that most of the same codebase can eventually run on iOS under the mentorship of Jasjeet Singh (jasje on IRC).

This post covers what the project was, everything I worked on, the parts that went wrong, what’s still left, and what the summer was actually like.

How I got here

I started contributing to ListenBrainz in December 2025. It was the first external open source project I’d worked on. Everything before that was coursework, side projects, or intra-college events.

My first PRs were small work which helped me a lot to understand the codebase from the ground, the shimmer effect across the Feed and Profile tabs, then extending search to cover playlists, artists, albums and tracks, plus some bug fixes. Small changes, but they taught me the codebase and how review works when nobody knows you and the code has to stand on its own.

I picked ListenBrainz because music is a constant in my day, whether I’m coding or not, and because I like that it treats your listening history as something you own.

The Problem

ListenBrainz has an Android app but no iOS version. A previous Swift attempt just duplicated the codebase, so every bug fix had to be written twice.

This project solves that by migrating to Kotlin Multiplatform, one shared codebase for both platforms. A large part of the work is replacing Android-only libraries with multiplatform equivalents across navigation, dependency injection and paging. Media playback is the harder case. ExoPlayer and WorkManager are tied too closely to Android to share, so both go behind common interfaces, with ExoPlayer on Android and AVPlayer on iOS underneath.

Getting this foundation right is what makes the rest cheap. Once it’s in place a feature or a bug fix is written once, instead of the same business logic being implemented twice and two apps being kept in sync by hand.

One thing genuinely can’t move. The notification listener that reads what’s playing in Spotify depends on an Android-only permission, and iOS has no equivalent to offer. Those screens stay Android-only. Everything else runs from one codebase on both platforms.

GSoC 2026: Modernize search storage format for the MusicBrainz database

Hello Everyone!

I’m Junaid (fettuccinae), an undergraduate Computer Science student at MGIT in India. This summer, I returned to MetaBrainz for my second GSoC project, where I worked on modernizing the MusicBrainz search under the mentorship of @kartikohri13 and @bitmap.

Project Overview:

MusicBrainz uses Apache Solr for search queries.
The previous implementation serialized all the response data into a single _store field.
The response writers reads _store, unmarshal the XML into a MusicBrainz XML Metadata Format (MMD) object and then serialize it again as XML or JSON for the response.
Few problems with this design are:
1. The indexer must construct a complete XML representation for every document, even though much of the same information is already available in normal Solr fields.
2. Most of the response data is stored in an opaque _store XML blob.

This project focused on moving the fields from one _store XML blob into their own flat fields (and JSON strings for nested fields).

The main goals of this project were:
1. Upgrade the Solr schema version from 1.5 to 1.7
2. Add fields (in configsets and indexer) to store all the data to be returned
3. Create response writers to return data from fields

The proposal for this project can be found here.

Welcome Summer of Code 2026 contributors!

We are excited to announce the 7 GSOC participants working with us this summer on MetaBrainz projects!
Our apologies for not publishing this sooner, in this complicated first part of the year we simply forgot the announcement, but rest assured the work is progressing on all projects.

As always, the selection process was incredibly tough. We received a great batch of proposals and had a limited number of slots.
We want to sincerely thank everyone who took the time to meet our community and submit a proposal with us!

The whole list of selected proposals can be found on the GSOC website but here is a TL;DR breakdown:

ListenBrainz proposals:

Integrate MusicBrainz events into ListenBrainz (Shirsak)

MusicBrainz has data about past and upcoming concerts that ListenBrainz users can’t see yet. This project will bring live music events directly into ListenBrainz, allowing you to discover shows tailored to your favorite artists.

Compose Multiplatform Migration of ListenBrainz-Android (Nirvan)

Currently, ListenBrainz has a native Android app but no iOS version. This project will migrate the app to a single, shared codebase using Kotlin Multiplatform. This means future features and bug fixes will launch on both Android and iOS at the same time.

Playlists Sorting and Organization (Yateen)

Giving ListenBrainz playlists a massive user-experience upgrade. Users will soon be able to search through playlists, organize them using custom tags, sort tracks (by artist, title, or date added), and convert their MusicBrainz collections straight into playlists.

MusicBrainz proposals:

Modernize search storage format for the MusicBrainz database (Junaid)

Cleaning up the under-the-hood engine that powers MusicBrainz search (Solr). By upgrading internal configurations and removing data redundancy, this project will optimize performance and make searching for music faster and more efficient.

GraphQL Server as a Musicbrainz API Alternative (Sreehari)

Building a fast, modern alternative way for external developers to request MusicBrainz data. This makes it significantly easier and more efficient for third-party developers to build apps using our database.

BookBrainz proposals:

Set Up BookBrainz for Internationalization (Garv)

Breaking down language barriers! BookBrainz is currently English-only. This project lays the technical groundwork to support multiple languages and sets up a BookBrainz project on translations.metabrainz.org where volunteer translators can start translating the site immediately.

Development of a new Calibre plugin for BookBrainz (Waqib)

Connecting BookBrainz with Calibre (the popular e-book management software). This plugin will allow Calibre users to automatically pull book metadata and collections directly from BookBrainz to organize their personal digital libraries.

What if you’re not in GSoC 2026?

Reading this and feeling inspired for contributing to the code still? Volunteer contributors are very welcome all year round even though we might have slightly less time available to help you during the summer. It is also putting you in an ideal situation for applying to next year’s GSoC. You can find some tips for applying to GSoC with us in one of our previous posts. When you are ready, join us on the MetaBrainz Matrix Channel and showcase your initiative and your skills!

GSoC 2025: Building Libretto, a Matrix Archiver

This post is also available on Jade’s blog

Hello! I’m Jade Ellis, AKA JadedBlueEyes. You might know me from my project with MetaBrainz last year – if not, I’m happy to have the chance to introduce myself. I’m an undergraduate Computer Science student at the University of Kent in England, a music enthusiast and (in my spare time) a climber.

The Setting

In September 2024, MetaBrainz switched from IRC to Matrix as our primary form of communication. Matrix is a more feature-rich alternative to IRC, with capabilities like replies, edits, and reactions, while still being open source and aligning with the principles of our project.

When MetaBrainz primarily used IRC, we had a piece of software called BrainzBot. This was a multi-functional Python app that, most importantly, created a web-accessible archive of all messages in the MetaBrainz channels. Thanks to the bridges between IRC and Matrix, BrainzBot continued to trundle along, but it couldn’t understand modern features like edits, replies, or media. The code itself was also becoming decrepit—a fork of an abandoned project, showing its age.

This led to my GSoC project: to build a replacement for BrainzBot’s archival function – a chat archiver that natively understands and preserves Matrix’s rich features.

GSoC 2025: Onboarding Revamp in ListenBrainz Android

Hi everyone,

I’m Hemang Mishra (hemang-mishra on IRC and hemang-mishra on GitHub). I’m currently a pre-final year student at IIIT Jabalpur, India. This summer, I had the opportunity to participate in Google Summer of Code with MetaBrainz. My mentor for the program was Jasjeet Singh (jasje on IRC).

I contributed to ListenBrainz Android, where I worked on revamping the onboarding experience, improving login, adding listen submission apps, integrating Listening Now, and setting up app updates. The journey has been both exciting and full of learning, and I’m truly grateful for this opportunity.

Project Overview

ListenBrainz is a powerful platform that helps track listening history, share music tastes, and build a community around music.

The main goals of my project were:

Revamping onboarding – introducing users to the app’s core features and handling permissions with clear rationale.
Improving login –replacing simple web pages with a custom Compose-based UI, and experimenting with the DOM tree of the web page to automate form submissions and token extraction in the background.
Listen submission apps – prompting users during onboarding to select which apps to collect listens from, preventing unwanted submissions.
Listening Now integration – adding “Listening Now” into BrainzPlayer.
App updates – enabling updates for both Play Store and non-Play Store (F-Droid or sideloaded) releases.

GSoC 2025: MetaBrainz Notification System

Hello, my name is Shaik Junaid (IRC nick fettuccinae and fettuccinae on GitHub). I’m an undergrad computer science student from MGIT, Hyderabad, India. My project focused on adding a central notification system for MetaBrainz.

Project Overview

This project’s idea was suggested to me by mentor @ruaok (AKA mayhem on IRC). I submitted my proposal on the MetaBrainz Forum and got it reviewed by @kartikohri13 (AKA lucifer on IRC), and finally got selected for GSoC 2025 .

A centralized notification management system will various MetaBrainz projects send notifications to users without rewriting boilerplate code. It will also keep users informed about the latest events and new features across projects. This is a goal bigger than the scope of a single GSoC project. To keep it reasonable, my project focused on implementing REST APIs, hosted on metabrainz.org, to manage notifications and user preferences for notifications. Additionally, I integrated the system with ListenBrainz to demonstrate its functionality.

The project spec sheet can be found here.

GSoC 2025: Advanced User Statistics Visualizations

Greetings, Everyone!

I am Granth Bagadia (holycow23 on IRC), an undergraduate Computer Science student at Birla Institute of Technology and Science (BITS), Pilani. This summer, I had the opportunity to participate in Google Summer of Code 2025 with MetaBrainz, where I worked on introducing advanced user statistics visualizations for ListenBrainz.

I was mentored by Ansh Goyal (ansh on IRC), Kartik Ohri (lucifer on IRC), and Nicolas Pelletier (monkey on IRC). This post summarizes my project, its outcomes, and my experience over the course of the program.

Project Overview

ListenBrainz already provided some listening statistics, but these were limited in scope and depth. My project set out to design and implement advanced statistics that could offer users more meaningful insights into their listening habits. Since ListenBrainz is a user-centric platform, the idea was to create features that would let listeners explore their behavior from multiple perspectives. My original proposal focused on introducing a few key statistics.

The core statistics included:

Genre Trends – showing what genres a user listens to at different hours of the day.
Era Statistics – highlighting which musical eras dominate a user’s listening history.
Artist Evolution – tracking how much a user listens to specific artists over time.

GSoC 2025: Importing Listening History Files in Listenbrainz

Hi Everyone!

I am Suvid Singhal (suvid on matrix), an undergraduate Computer Science student at Birla Institute of Technology and Science (BITS), Pilani. I took part in the Google Summer of Code 2025 and have been contributing to Metabrainz Foundation since December 2024. My GSoC project was to develop a file-based listening history importer for ListenBrainz. The project was mentored by Lucifer and Monkey.

Project Overview

Listenbrainz is a platform to track your music habits, discover new music and share your music taste with the community. A feature I missed after creating my ListenBrainz account and connecting Spotify was the ability to see my complete Spotify listening history. My project addresses this gap by allowing users to export their extended streaming history from Spotify and import it into ListenBrainz. Additionally, users can import backups from their old ListenBrainz accounts. With the foundation ready, it will be simpler to add support for more file importers in future. This makes transitioning to Listenbrainz easier.

The importer can be accessed here.