Join us for a hackathon in Copenhagen, Denmark, on 23rd October 2026, from 12:30 to 18:00. The event is sponsored by Futurewei and organised in collaboration with Dr Carla Griggio and the mInt Research Lab on User-Centered Messaging Interoperability at the Department of Computer Science, Aalborg University.
Don't forget to grab your ticket!
There are many activities to take part in during the hackathon, including:
The Department of Computer Science at Aalborg University has set a challenge to make differences in data handling more visible in Matrix. Why not try to come up with a solution?
Bridges let Matrix users talk with people on Telegram, Slack, Discord, and other platforms, which greatly extends Matrix's reach. When a message crosses a bridge, it enters a system with different rules: it may be stored on the other platform's servers, kept longer than your own server's retention policy allows, or be visible to people and services you didn't expect. Matrix already offers some hints that a room is bridged, such as bridge information in room settings and recognizable bridged user accounts, but these mostly tell you that a bridge exists, not what it means for your messages, and they are easy to miss. Different Matrix clients may also do different things with a message once it is decrypted, such as sending a voice message to a third-party service for transcription, and the sender has no way of knowing.
How could Matrix conversations let people know when the conditions governing their messages change? Explore this from the user interface side, the protocol side, or both!
User Interface: How should this appear to users? For example, as a notice when a bridged participant joins, a marker on a profile, a label on individual messages, or a warning before sending. Sketches, mockups, a proof of concept in an existing client, or a draft protocol proposal are all welcome.
Protocol: What would bridges and clients need to declare about how they handle messages (for example encryption, retention and deletion, and who else can access the content), and how could that be expressed as an extension to Matrix?
The address is: Aalborg Universitet København, A. C. Meyers Vænge 15, 2450 København, Denmark (Rooms 3.084A and 3.084B)
The hackathon marks the end of the conference and takes place at Aalborg University in Copenhagen, Denmark, following the main conference in Malmö, Sweden.
Travelling between the two locations is straightforward. You can either take a train on the Öresundståg network from Malmö to Ørestad and transfer to bus 8A, getting off at Sluseholmen St, or continue on the Öresundståg network to Copenhagen Central Station (København H) and then take metro line M4 to Sluseholmen St.
Public transport tickets can be purchased easily through the Skånetrafiken app. The app is available in English.
Whilst at the venue, Aalborg University’s map app will help you navigate the campus and surrounding area. The app is available in English.
Denmark is part of the Schengen Area, so it is easy to travel there from many European countries, including Sweden. Please also note that Denmark uses the Danish krone (DKK), not the euro, as its currency.
Refreshments at the hackathon will cater to a range of dietary needs and preferences, including vegetarian, vegan and gluten-free options.
Please note that the health and safety policies, as well as the accessibility information, that apply to the main conference also apply to the hackathon. Please see the relevant information for more details.
