Centralized proprietary collaboration software has recently faced a grown scepticism. In November 2022, the French Government officially asked schools to not use Google's and Microsoft's collaboration services. Luckily there are open source alternatives that can be self-hosted to give individuals and institutions more contol over their data. While users thus do no more need to rely on big companies, they still need to trust the system administrators hosting the software to respect the user's privacy.

CryptPad is an end-to-end encrypted open source collaboration suite. It seeks to reconcile collaboration and privacy. Users make changes to documents and these are encrypted by their client (web browser) before being sent to the server for real-time synchronization. CryptPad hides the technicalities of encryption from its users and provides a clean and intuitive interface to ease fast adaption. In this talk I will present how CryptPad keeps the user's data private and protects them against a passively sniffing server. I will show why we combine end-to-end encryption with open source and will talk about the ecosystem around CryptPad.