Germ, a new startup co-founded by Tessa Brown and Mark Xue, is launching its end-to-end encrypted direct messages for the Bluesky social network into beta this week, offering users a more secure messaging alternative.
The technology Germ is developing, much of which is open-sourced, could potentially be integrated into Bluesky’s own app in the future, enabling native encrypted messaging. This development is significant as it distinguishes Germ from established end-to-end encrypted platforms like iMessage, Signal, and WhatsApp by leveraging newer technologies such as Messaging Layer Security (MLS) and the AT Protocol (ATProto), which powers Bluesky.
Unlike some messaging apps that rely on phone numbers, Germ integrates directly with ATProto, allowing users to securely communicate with their Bluesky connections and across the broader open social web, including apps like Flashes and Skylight. Germ also offers enhanced user control features, enabling users to customize their DM settings to accept messages only from those they follow on Bluesky or restrict message initiation to themselves. Furthermore, blocking a user in Germ can extend beyond the platform, blocking them across Bluesky and other ATProto-powered applications.
Tessa Brown, Germ’s CEO and a communications scholar, emphasized the importance of private communication for healthy social networks, stating, “We know that, psychologically, you can’t build a good relationship with people if you feel like you’re being stared at and manipulated all the time. And that’s really what social media is today.” Brown believes that end-to-end encrypted messaging is a crucial aspect of the future of social media and communication.
Mark Xue, formerly a privacy engineer at Apple, sought to move away from phone numbers as the foundation for secure communication, believing it to be an outdated approach. Germ utilizes a “magic link” system to facilitate chats, generating a link for each user that is pasted into their Bluesky bio. When another Bluesky user on iOS clicks the link, they can immediately start a conversation without needing to download a separate app from the App Store, made possible through Apple’s App Clips technology.
The “magic link” is a cryptographic key that authenticates the user’s ATProto identity, confirming their association with the specific Bluesky handle. Users can also choose to install the full Germ iOS app, which provides additional features such as access to their friends list and Bluesky pairing.
Brown expressed enthusiasm about building within the Bluesky community, highlighting the platform’s growing cultural influence and the presence of prominent figures like Barack Obama and Hillary Clinton. Given Germ’s progress in developing encrypted messaging technology, Brown hopes that its protocol will be adopted by Bluesky and other platforms in the future.
While currently free, Germ may introduce a premium subscription model with advanced services like private AI, personalization tools, and other enhancements. The four-person startup has secured pre-seed funding from angel investors, including an MLS co-author and trust and safety experts, with institutional investors including K5 Global and Mozilla Ventures. Germ intends to raise further funding to develop an Android version of the app.
