At the end of 2023, we became aware of an unofficial Matrix instance, matrix.epfl.ch, hosted by EPFL's Center for Imaging, that was open to the entire EPFL community. Thinking ahead and planning to eventually move the users of matrix.c4dt.org to this EPFL-wide instance, C4DT reached out to Edward Andò to offer our support bolstering matrix.epfl.ch's team, which was readily welcomed. Edward Andò is principal scientist at the Center for Imaging at EPFL and started the matrix.epfl.ch project because he needed a reliable chat application that he could trust.

The strategy of the Matrix team, composed of Edward Andò and Carine Dengler, was two-pronged: on the one hand, consolidating the existing service, and on the other hand, officializing the service within EPFL to ensure its long-term viability.

To consolidate matrix.epfl.ch, we took several steps. Most notably, we established regular admin meetings for decision-taking and pair-programming, put a tool in place to manage sensitive information, migrated the project to EPFL's GitLab to facilitate collaboration, created a dedicated test environment for new versions, and integrated the live instance into C4DT's monitoring.

To engage stakeholders and gather support for an official EPFL Matrix instance, we met directly with key individuals from different units within EPFL. We also presented the project at various internal events, most notably the Forum SI organized by the central IT services of EPFL. Furthermore, in collaboration with EPFL's legal team, we drafted the Terms of Use of matrix.epfl.ch.

Crucially, despite almost no effort having been made to promote matrix.epfl.ch to the larger EPFL community, the service experienced a remarkable surge in its user base, from under a 100 registered users at the beginning of 2024 to over 900 mid of 2025, with over 250 daily active users. That this increase is largely attributable to word-of-mouth alone demonstrates significant community interest in this service.