Wire's Proteus encryption protocol was an early fork of what became the Signal Protocol, creating a parallel secure messaging implementation with a very different business model.
Proteus is Wire's implementation of the Double Ratchet algorithm, forked from early pre-Signal protocol code. It provides end-to-end encryption for messages, calls, and file transfers. Wire also developed the MLS (Messaging Layer Security) protocol as a successor for group conversations.
In the early 2010s, Open Whisper Systems (led by Moxie Marlinspike) was developing the cryptographic protocols that would become the Signal Protocol — the gold standard for end-to-end encrypted messaging. The code was open source, and several projects built on early versions of it.
Wire Swiss GmbH, founded in 2012 by Skype co-founder Janus Friis and a team of former Skype engineers, forked an early version of this pre-Signal code in 2014 to create the Proteus protocol. They used it as the encryption layer for Wire, a slick, enterprise-focused messaging app that launched in December 2014. Wire positioned itself differently from Signal — targeting businesses and organizations rather than privacy activists.
Wire open-sourced its client code in July 2016 and completed open-sourcing the server code by September 2017 under AGPL — a move that earned praise from the security community. An independent audit by Waterloo researchers found the implementation generally solid with 'relatively minor' issues.
But Wire's privacy story got complicated. In 2016, it was discovered that Wire stored contact metadata in plaintext on its servers. In November 2018, the privacy policy changed to allow data sharing 'if necessary or required by law.' In late 2019, Wire's holding company moved from Luxembourg to the United States, raising jurisdiction concerns. It moved back to Germany in 2020 after backlash, but trust had been shaken.
Wire continues to operate as an enterprise-focused secure messenger, but the privacy community largely moved to Signal. The Proteus protocol, while technically sound, never achieved the widespread adoption or standardization of the Signal Protocol it forked from.
Wire forks early Signal protocol code to create Proteus
Wire messenger launches publicly
Wire open-sources client applications
Wire completes open-sourcing server code under AGPL
Wire holding moves to US, sparking jurisdiction concerns
Wire's Proteus fork demonstrated that the Signal Protocol's concepts could be adapted for enterprise contexts, but also showed the tension between enterprise business models and consumer privacy expectations. The protocol's fork illustrates how even the best cryptographic foundations can be undermined by metadata handling and corporate governance decisions.