Chaos Computer Club - recent events feed (high quality)

The Matrix Rust SDK is one of the most complete, mature, and performant SDK in the world. To illustrate our point, we will show off how to develop a Matrix CLI client from scratch with the Rust SDK live on stage, step by step, up to having a fully functional client, with a room list, a timeline, the ability to send and to receive messages, along with full end-to-end encryption support. The Matrix Rust SDK is one of the most complete SDK in the world. It's becoming really mature: more and more clients are relying on it due to its...

A vanilla matrix deployment already offers a lot options and is part of many digital sovereign communication solutions (and for good reasons). It can solve some of its tech dependency issues and can be a great alternative to Teams, Slack, WhatsApp etc. However, some organizational requirements still require more careful thought and planning than one might expect at first glance. This talk summarizes some of our experiences with often overlooked challenges, decisions with potentially far-reaching consequences and possible solutions/approaches when trying to implement a Matrix-Deployment for bigger organizations like schools, universities or other public organizations and similar projects. We...

This talk is about how feature asymmetries between interoperable messaging apps may disrupt users' online self-presentation, that is, how they choose what features to use with different groups of people to control the impression they form of them. Most users of messaging apps have their strategies to uphold some specific “persona”, if it is sending GIFs to add a humorous tone to the conversation, intentionally using dots at the end of messages to seem more intelligent or professional in front of their boss, or how they resonate when choosing a Snapchat avatar versus their profile picture for Teams. However, in inte...

This presentation outlines the development experience of a post-quantum cryptography (PQC) extension for the vodozemac library, tailored for its use in MSG GOV, a Matrix-powered E2EE messenger for the Brazilian federal government. Our hybrid design is adapted to support multiple PQC algorithms, including ML-KEM and Brazil's state-mandated cryptography. The talk details the practical software engineering challenges associated with the hybrid integration of flexible PQC features into the Matrix protocol, extending both the key agreement and the Double Ratchet algorithm while preserving compatibility. Licensed to the public under https://creativecommons.org/licenses/by-sa/4.0/ about this event: https://cfp.2026.matrix.org...

The Matrix Rust SDK has grown from an experimental client SDK into the foundation that powers Element X and other Matrix applications. Along the way, it has gained support for major Matrix features while tackling some interesting engineering challenges. In this talk, we'll explore recent additions to the SDK, including threads, spaces, QR code login, shared encrypted history, migration from Element Classic to Element X, and the centralized redecryption mechanism. We'll look at the problems these features were designed to solve, the architectural decisions behind them, and some of the lessons learned along the way. This talk is aimed at...

Digital Sovereignty is on every lips, however whilst the tech is here, we have yet to find a financially sustainable solution to it. The tragedy of the commons of open source is not new, but we’ve got to the point of needing to solve it if we really want organisations to be sovereign and resilient whilst use secure and polished products. We all know (or will know by the end of the conference!) that Matrix is the ideal answer for any organisation looking to break free from vendor lock-in for their communications, not only because of its intrinsic properties of...

Convincing users to move to NI2CE messenger and move away from the tools they are used to working with remains an issue. I would like to share my thoughts and discuss how other organisations where the use of Matrix messengers is optional deal with this. NI2CE is a messenger solution that we deployed for NATO users to provide a safer and more private alternative for the widespread use of Whatsapp and Signal. The use of NI2CE is optional as users need to install it on a personal device for mobile use. I had hoped that reaching a...

When you operate communication infrastructure for one of Europe's largest defense organizations, "good enough" is never good enough. At BWI, we do not just run Matrix. We trust in the idea behind it: that secure, open communication should be a public good. When we introduced Matrix into the Bundeswehr, we made a deliberate decision: everything, always, end-to-end encrypted. No exceptions, no fallbacks. That single switch revealed the hard problems. Olm and Megolm, built on the Signal Protocol, are the gold standard of modern encryption, but they were not designed for large rooms with thousands of participants at government scale. Those...

Are you operating a large server, bridge or bot? Are you managing lots of spaces or rooms? Do you sometimes need to modify rooms outside of your regular account? Try Matrix Wrench. It's is a powerful, open-source web app to view and edit room states. It works with access tokens from users and AppServices. In my time at the Matrix.org bridges team, I had worked on a few of the largest bridges operated at the time. Routine tasks included supporting the community leaders, e.g. when room admins had made mistakes or became inactive. With the administrator role of...

Side effects of modern healthcare communication: data breaches, €1.2 billion in GDPR fines last year, and a group chat with 47 nurses. The treatment is a messaging app. The one you're thinking of isn't it. Walk into any ward, GP surgery, home care team, or therapy practice in Europe and you'll find the same thing: clinicians on WhatsApp. Not because they don't know better — because it works, it's fast, and the secure alternative breaks the workflow. This talk is a frank look at why Europe's most-used clinical tool isn't a clinical tool. The answer cuts across the entire care continuum: from large hosp...

When you operate communication infrastructure for one of Europe's largest defense organizations, "good enough" is never good enough. At BWI, we do not just run Matrix. We trust in the idea behind it: that secure, open communication should be a public good. This talk traces that journey. It begins with our decision to adopt Matrix as the sovereign communication backbone for the German armed forces, and the architectural ambition that drives our work: a communication stack where the functional core is formally verifiable, and memory safety is a given everywhere else. An engineering target we are actively working toward. As...

At Element, we've been thinking about how you can be sure you are chatting to the right person, not an intruder, without reading out numbers or emoji over a video call. One approach we've been experimenting with is the use of X.509 certificates issued by a trusted certificate authority. I'll be talking about how this helps (and when it doesn't), as well as covering some technical details of the implementation. This talk is aimed at people interested in how we can improve the user experience of encryption of Matrix. I'll assume familiarity with concepts around encryption in Matrix such as...

Famedly talks about the developments in the Austrian healthcare market and the adoption of matrix as the messenger protocol of choice. Leaning into the similarities and differences between Germany and Austria. On January 1, 2025, Austria officially discontinued the use of fax machines for exchanging patient data. While a necessary digital milestone, this abrupt shift initially led to a highly fragmented landscape of disconnected replacement solutions. Recognizing the looming interoperability crisis as early as 2024, state and federal institutions began searching for a unified, scalable alternative. Drawing inspiration from Germany, the TI Messenger was quickly identified as a highly promising blueprint for a...

Governments increasingly need messaging that is secure, federated, and independent from foreign proprietary platforms, but turning an open protocol into a deployable government tool raises hard questions about sovereignty, infrastructure, and identity. This talk presents MSG GOV, a Matrix-based messaging platform for the Brazilian federal government. Today, it targets a defined set of public servants rather than the entire population or every government employee — a deliberate, controlled scope as the platform matures. We plan to share the factors that drove the need for a sovereign messaging app in the first place and to dig into how MSG GOV is built an...

Matrix was designed around strong end-to-end encryption and user-controlled trust. While this model is ideal for private communication, large public-sector and critical infrastructure deployments face additional requirements that go beyond traditional E2EE. This talk explores the challenges of operating Matrix within one of Europe's largest sovereign and security-critical IT infrastructures, where legal archiving obligations, compliance requirements, incident handling, automation and long-term information governance must coexist with modern encrypted communication. We discuss why classic end-to-end encryption is not always sufficient in enterprise environments and examine the concept of End-to-Organization Encryption (E2OE) as a potential architectural approach. Rather than focusing...

The hardest part of modernizing healthcare communication is not building a new platform. It is preserving decades of existing integrations while enabling an entirely new communication model. Germany's healthcare sector currently relies on two communication systems with very different characteristics. KIM is the widely adopted communication backbone of the healthcare system. It enables critical workflows such as electronic certificates of incapacity for work and is deeply integrated into healthcare information systems. However, its architecture is based on traditional email technologies and on infrastructure that will have to evolve significantly in the coming years. The TI-Messenger, based on Matrix, provides a...

Intended for people who don't know much about encryption or Matrix, this session will give an overview of how your messages are kept safe, using end-to-end encryption. We'll very briefly review what we are trying to do: be sure who we're talking to, and be sure no-one else can read our messages. Then we'll discuss how Matrix does this: devices talk to each other with something called Olm, and messages in rooms use Megolm. By the end of this session you should be confident talking about how Matrix keeps your data safe, and you should know enough that you are...

In April 2025, a new homeserver burst onto the scene. Soon enough, hundreds of servers were running this mysterious new software - and the momentum didn't drop. Today, more than one and a half thousand servers on the public federation run [Continuwuity](https://continuwuity.org/). That leads to some questions. Where did it come from? What happened? Where is it going? Well, We've got anwers for all of that. Right here. Exclusively. This is a breakdown from the team behind the ~~mystery~~ well-regarded open source project, going over all of that and more. You know you're interested. Licensed to the public...

In 2026, Element's Integrations team set out to make Matrix the productivity layer for sovereign workplaces, the place where your files, documents, projects, and calendar don't just link out, but live alongside your conversations. We'll walk through what we built, how we approached the hard problems, and what it means for organisations already running open-source workplace stacks. We'll also look at where this is headed and what it'll take for the wider Matrix ecosystem to build it together. Licensed to the public under https://creativecommons.org/licenses/by-sa/4.0/ about this event: https://cfp.2026.matrix.org/matrix-conference-2026/talk/JVU9AL/

Last year we started the endeavour of bringing Matrix and MLS together. The work on this subject led to some pretty exciting developments. Here you will be the first to learn about them! Licensed to the public under https://creativecommons.org/licenses/by-sa/4.0/ about this event: https://cfp.2026.matrix.org/matrix-conference-2026/talk/G9XJTA/

The Matrix.org Foundation is the key to Matrix' independence from any commercial vendor. It exists to protect the neutrality of the Matrix protocol, promote Matrix as an open standard, give a voice to the members of the ecosystem and ensure trust and safety within the open network. This keynote will give an overview of the latest about the Foundation and will include a presentation from the Governing Board on the activities led by the various Committees and Working Groups. Licensed to the public under https://creativecommons.org/licenses/by-sa/4.0/ about this event: https://cfp.2026.matrix.org/matrix-conference-2026/talk/FYKJMY/

In a comprehensive digital workspace, the ultimate measure of success for Matrix is invisibility. End-users shouldn't manage a separate Matrix profile, understand what a homeserver is, or manually exchange Matrix IDs. But how do you take a protocol designed to be the center of its own universe and cleanly relegate it to a silent, powerful chat engine under the hood of a broader platform? This talk explores the architectural reality of "disappearing" Matrix into a cloud collaborative platform. We will explore how to hide Matrix-flavored concepts to users, and map platform-native user management or ACLs onto Matrix. By looking at...

In our talk, we would like to give conference participants an insight into practical use cases for the Matrix solution. We will cover projects in the healthcare sector, external security, and public administration. We will discuss the approach taken for a Matrix implementation project. We will share insights on how to successfully execute such a complex project, using the TK Messenger and the “Bundes-Messenger/Bundeswehr-Messenger" as examples. Afterwards, we will outline the Proof-of-Concept process within the public administration (Project Neo). Licensed to the public under https://creativecommons.org/licenses/by-sa/4.0/ about this event: https://cfp.2026.matrix.org/matrix-conference-2026/talk/EYBZT9/

Just days before this conference, the European Commission adopted the **European Technological Sovereignty Package**, placing open source explicitly at the centre of Europe's digital strategy for the first time. The timing is not coincidental. It is the political response to a structural dependency Europe can no longer afford to ignore: critical infrastructure — including healthcare — running on platforms controlled by others. This talk makes a practical argument: digital sovereignty has moved from political rhetoric to **procurement reality**. Across Europe, more than 20 governments have already chosen Matrix as their foundation for sovereign, vendor-agnostic communication — from Germany's Bundeswehr and BundesMessenger to France's Tchap and La...

The European Commission defines tech sovereignty as Europe’s ability to act independently in the digital world by developing and controlling key technologies, data, and infrastructure, while reducing reliance on non-EU providers. On June 3, the European Commission has published a tech sovereignty package. What’s included in the package? What’s positive? What the Commission didn’t get quite right and can it be fixed? And what’s in it for Matrix and Free and Open Source Software in general? The talk will provide a gentle introduction into some of the elements of the tech sovereignty package and try to answer all...

Over five decades, is the largest strategic partner for common, trusted, and cybersecure digital foundations across the entire UN system. Today, UNICC serves over 100 UN entities and other international organizations, operating in a global environment where secure, cross-agency collaboration is essential to fulfilling its mandates. Therefore, UNICC is uniquely positioned to identify and promote the reuse of open-source solutions across the UN system and beyond. Operating within the UN context requires strict adherence to institutional independence, technological neutrality, data privacy, and digital sovereignty. Matrix’s open, decentralized standard has helped UNICC ensure that sensitive inter-agency communications, crisis management, and incident re...

Waldur is a multi-tenant cloud and HPC resource-management platform. In Estonia it powers the state cloud (Riigipilv) and the national scientific computing infrastructure (ETAIS), where deployments routinely involve personal and sensitive data. Yet support for all of it happens across scattered channels: Slack, Signal, email, whatever a given user reaches for. The context for any single deployment is split across all of them. To debug a problem you reconstruct the story from fragments in different apps, there is no durable history tied to the project, and sensitive conversations end up sitting in third-party consumer tools. We are building a Matrix...

2026 has seen the resurgence of Next Generation Matrix research funded by Element, as we get back to futureproofing Matrix for the medium-long term. The main project has been the return to P2P Matrix: embedding homeservers inside modern Matrix clients, speaking the very latest Matrix room versions, supporting arbitrary overlay networks. This opens up the world of Matrix for pure mesh communications, and can radically improve metadata footprint (given in a world with no servers, there's nowhere for metadata to gather). Funded by the Dutch Government, we announced this at last year's Matrix Conference in the Matrix State of the...

Every organization that adopts Matrix federation makes the protocol more valuable. Every gap they hit makes adoption harder. Rocket.Chat runs Matrix federation in production for government, defence, and critical infrastructure organizations, and that work shows where the protocol already meets customer expectations, and where it can go further. This talk shares our findings from real-world implementation conversations, findings from adoption, and proposals for native capabilities. Licensed to the public under https://creativecommons.org/licenses/by-sa/4.0/ about this event: https://cfp.2026.matrix.org/matrix-conference-2026/talk/3GTLFM/

The privacy paradox (the theory that people say they care about their privacy but behave as if they do not), assumes that user behaviours are irrational, uninformed, and based on choosing convenience above their own data protection. My research points to a different perspective: people do care, and they also behave inconsistently, but not always out of convenience. At its core, it seems that people behave inconsistently because they feel they have no agency and that “there is no point” in trying to protect their personal information. In this sense, we all live more in a state of privacy helplessness than...

Digital sovereignty is a board-level priority, but ambition often outpaces reality. In this session, Forrester analyst Dario Maisto presents findings from his latest report, drawing a clear line between sovereignty, privacy, and security, and examining the practical challenges organisations face in reducing dependency on dominant tech stacks, from productivity suites to communication. He explores how open standards and open source can support sovereignty goals, introducing a Minimum Viable Sovereignty framework for setting realistic targets. The session also addresses the limits of open source, including project health, maintainer sustainability, and commercial support, as key factors in mission-critical viability, leaving attendees with...

Introducing a new communication tool into an existing organisation or community usually means training users and addressing their common pain points as best as possible. Over the last few years, Element Server Suite (ESS) has empowered administrators to integrate Element in a way that makes sense for their organisations, through tools like Element Admin and recent improvements in the rest of the Matrix stack. This talk will go through what the Element stack has to offer in terms of administration tooling, UX improvements for onboarding new users and integration with existing user directories. This includes concrete user-facing features like QR...

Currently user search can only be done locally, which would at best get a list of all users known to the server. This talk aims at explaining the research we did regarding speccing and implementing a spec change proposal for the user federated search (MSC4258). We will also explained the different solutions we thought about and the associated tradeoffs regarding data privacy, performance and complexity. This talk is also about a collaboration between 2 public sector teams from 2 different countries :) Licensed to the public under https://creativecommons.org/licenses/by-sa/4.0/ about this event: https://cfp.2026.matrix.org/matrix-conference-2026/talk/V9PXRV/

Enhancing open standards and data ownership within its ecosystem, the European Commission is walking the (sovereign) talk by introducing a new Digital Workplace service powered by Matrix / Element. This talk walks you through the EC's journey from early architecture decisions to deploying a production ready communication service. We will share the practical reality of integrating Matrix into a large-scale institutional ecosystem - balancing strict security and compliance requirements with user experience and the key lessons learned along the way. Licensed to the public under https://creativecommons.org/licenses/by-sa/4.0/ about this event: https://cfp.2026.matrix.org/matrix-conference-2026/talk/YHV8XB/

Robrix is a "new" FOSS Matrix client written entirely from scratch in Rust, with some cool power user features like a **dockable-tabs view** of multiple rooms side-by-side, just like your favorite IDE. It's simple and flexible enough for casual chatters as well, and can seamlessly transition into a sleek mobile-friendly adaptive UI for narrow screens. Robrix runs smoothly and consistently across mobile & desktop platforms, thanks to the underlying Makepad UI toolkit and Robius abstraction crates, which we also wrote ourselves in Rust. After several years of hard work on those components, we have finally reached the milestone of publishing Robrix...

The federation protocol is how Matrix homeservers communicate between each other. In private federations this isn't particularly challenging as the network is trusted but in the public federation this isn't true. This talk dives into what protocol improvements are in the works to make the public federation more secure against Byzantine actors, particularly against "backdating": intentional misuse of the concurrency primitives to manipulate the authorisation algorithm. We'll explore why this problem is hard, what some of the failure modes are, and how we are working on addressing them. Some of this work was presented in a [peer-reviewed article](https://dl...

To make the most of the sovereignty and interoperability enabled by Matrix, governments need to deploy at scale; across multiple organisations within their own country, between partner countries and mission partner environments. At an even larger scale, they may also need to support government to citizen communications - literally tens or even hundreds of millions of people. This session explores what’s required to deliver these types of production environments straight out of the box. We'll cover server-side interoperability, mixing and matching Element Server Suite Pro with other Matrix-based solutions without friction, and how to make federation genuinely easy to de...

Matrix already provides the essential primitives for a decentralized calendar: room memberships, federated state exchange, spaces, and support for custom event and room types. This session explores the technical integration of RFC 8984 (JSCalendar) within the Matrix protocol. We will examine how the JSON-based representation of JSCalendar can be mapped to Matrix state events and what pieces are missing. The presentation concludes with a live demonstration of a working prototype within Tammy. Licensed to the public under https://creativecommons.org/licenses/by-sa/4.0/ about this event: https://cfp.2026.matrix.org/matrix-conference-2026/talk/WWLM98/

NeoBoard, the open-source real-time collaborative whiteboard built on the Matrix protocol, has come a long way since its first appearance at the Matrix Conference. In this talk, Nordeck's CEO gives an honest account of where the product stands today — the architecture, the open-source release, the feature roadmap — and announces some surprises that take NeoBoard beyond the developer community and into everyday use. A concise overview of the current state: the dual form factor (Matrix widget for Element Web and a standalone Matrix client), the open-source release under AGPL-3.0, the infinite canvas, CRDT-based real-time collaboration via MatrixRTC, and the product's place with...

Element Call already proves what is possible with MatrixRTC: decentralised, federated, end-to-end encrypted video and voice calls powered entirely by the Matrix protocol — but most of the Matrix ecosystem hasn't yet adopted it. To change this we need to build an ecosystem around MatrixRTC that is as vibrant as Matix itself. This talk outlines the vision of components for such an ecosystem and consolidates all the details required to efficiently build on top of MatrixRTC or add support to clients and sdks. This talk starts with a quick tour of MatrixRTC from the ground up. We start with the core sp...