Documentation and downloads
Evaluate without asking our permission.
The core of Crypto is open: the network code, the installers and the technical documentation are public. Everything you need to evaluate the product is below. No form to fill in.
Download the app
Windows
Windows 10 or 11, 64-bit PC. Take the file whose name ends in -setup.exe
Get it via GitHub →macOS
Mac with Apple silicon (M1 or newer). Take the .dmg file. Intel Macs are not covered yet
Get it via GitHub →Linux
64-bit PC. Debian or Ubuntu: the .deb file. Fedora or RHEL: the .rpm. Any other distribution: the .AppImage
Get it via GitHub →The first time you open it, Windows and macOS will show a warning. That is expected: our installers are not yet signed with Microsoft or Apple. On Windows, click “More info”, then “Run anyway”. On macOS, right-click the app, then “Open”. Linux shows no warning. Since that warning tells you nothing about whether the file is genuine, check its fingerprint instead: every release lists the expected fingerprint of each file and the command that compares them. Later updates are properly signed: the app refuses any update whose signature is not ours.
The network components (the authority that keeps the directory, the relays, the mailboxes, the servers that carry call audio) install from the public Gotham repository under the AGPLv3 free-software licence: anyone can read that code, check it and host it. The client application and the enterprise features fall under a separate commercial licence and their code is not public.
For your evaluation file
Functional specification
Encryption, the relay network, mailboxes, governance, the data kept on the device, calls. The full reference, written for an engineer.
Threat model
Who Crypto protects you from, who it does not, and the assumptions you have to accept. The document to hand to your risk team.
Audit method
72 findings examined, 30 dismissed after checking, 30 fixed so far. Each fix comes with a test that keeps the problem from coming back, in the network's public repository.
Source code
The Gotham network, written in Rust, under the AGPLv3 free-software licence: protocol, relays, directory, authority. The repository is what counts, this site is only its summary. The client application is proprietary and is not part of it.
Missing a document you cannot find here, an architecture file or answers to a security questionnaire? Write to us: an engineer replies.