Open source guarantees security
Our choice to publish the entire client code on GitHub for all Tuta apps – Windows, macOS, Linux, Android, iOS and web clients – means that anyone can audit the code and verify that Tuta protects the security and privacy of your data to the maximum. It’s a guarantee that there is no backdoor in the end-to-end encryption. It also means that any bugs or even potential vulnerabilities get noticed quickly and we’re able to fix them much faster than closed-source email providers.
At Tuta we follow Linus's Law: "Given enough eyeballs, all bugs are shallow."
Publicly audited
Before the public release of Tuta, all our apps have been audited by independent security experts. In an extensive penetration test, experts from SySS GmbH have not been able to hack into our system or retrieve any encrypted data. But it’s even better to have as many layers of protection as possible when it comes to your data privacy and security.
Published as GPLv3
For these reasons it was also crucial for us to publish the entire client code for Tuta under GPLv3 as free software. What is more, we even built our own captcha and push notification service, in order to make sure that the software is free. And, we don’t need to rely on integrating with any closed-source third-party services, for instance by using Google Push. This is part of what makes Tuta the most secure email service in the world.
![Tuta GitHub repo: All client code of Tuta is published as open source on GitHub.](/_astro/github-tutanota-screenshot.CctBTiLo_2c8nDD.png)
App on F-Droid
We’re proud of the fact that Tuta was the first open source email app available on F-Droid. We must be in full control of the open source code to offer maximum security and privacy. Our focus on free and open source software (FOSS) and encryption combined with our deep respect for your right to privacy, makes Tuta the best email service for businesses and private users who care about protecting their data.
Build-your-own customized version of Tuta
By publishing our code, we enable everyone to build and run their own custom version of email clients for Linux and F-Droid operating systems, based on their custom needs and preferences, or even just for fun. As developers we love Linux, GIMP, OpenOffice and all the other great open-source tools out there. That’s why we invested time and effort to complete the documentation to enable people to build and run their own version of Tuta locally.
In 2017 we joined the Open Invention Network (OIN) to support and strengthen the FOSS community. OIN enables open source developers to freely develop and share their work while being protected from patent suits. To push back against patent trolls, patent protection and non-aggression agreements are of huge importance. OIN fosters a safe patent environment for developers of Linux/Open Source-based software.
In OIN all members grant each other free access to the Linux System patents they may hold. This way OIN protects its members from potential patent fights over the Linux System and guarantees the free and open development of the Linux environment.
Thriving Community
Tuta’s success is closely linked with our thriving community. Tuta is not backed by large Venture Capitalists, but built by a team of open source enthusiasts who build Tuta for the people. Our intense interaction with our users helps us to constantly improve Tuta.
From translation support to pull-requests to finding new team members, our community has a large share in how the future of Tuta is shaped. We actively invite you to give feedback and to support us in our fight for privacy.
Since the majority of our users are not developers, our number one goal is to offer an encrypted tool so easy that anybody can use it. Many of you have offered to help by translating Tuta, and we’re enormously grateful for everyone’s support! We never expected to receive so much support from our community - not just with the translation, but also by spreading the word via Social Media or by directly recommending Tuta to friends and family. We are a small team focusing all our efforts on development so any support - even if it's a simple 'Hi, keep up the good work' - empowers and motivates us to make Tuta a little bit better every day.