Our mission is to defend human rights and democracy through building software that is essential for digital freedom and privacy protection for all Internet users.

ProtonMail was founded in 2014 by a group of scientists who met at the European Organization for Nuclear Research (CERN). And since its inception, the company has grown at a fast pace and today has over 26 million users. Our principal product, ProtonMail, is the world’s largest secure email service. Our second product, ProtonVPN, is one of the world’s most popular VPN services. Our vision is to build an Internet platform for the protection of digital rights, and we are also developing additional products such as ProtonCalendar, ProtonDrive, and much more.

Proton users include leaders of the Hong Kong protest movement, New York Times journalists, some of the world’s largest corporations, and millions of ordinary citizens from over 180 countries. Our team is diverse and dynamic, representing over 30 different nationalities, with offices in Geneva, Zurich, Prague, Vilnius, Skopje, San Francisco, and Taipei.

While the open nature of email is great for interoperability, accessibility and freedom from centralized control, it also creates challenging email delivery problems. Any server in the world can send email to any other email server. Many systems must work together at ProtonMail to mitigate spam and virus attacks, do proper authentication to prevent email spoofing, and finally deliver email to the right place.

You will join a growing mail delivery team to build and operate sophisticated backend systems that send, receive, and filter email. This team contains a mix of senior software engineers and devops/site reliability engineers.

Your work will directly improve the user experience and digital security of millions of people around the world. You should have extensive experience designing and developing scalable and highly-available systems.

What you will do:

• Improve our mail delivery pipeline (MTA, milters, custom anti-spam systems)
• Improve and monitor delivery statistics
• Protect users against various attacks such as phishing, list bombing, and spoofing
• Automate, deploy, monitor, and troubleshoot critical mail systems

• Software engineering experience with production systems (Python, PHP, C)
• Experienced with Linux and web technologies (DNS, TLS, SMTP)
• Bonus: worked with production mail systems (Postfix, SpamAssassin)

Why you should join Proton:

• We work on interesting, challenging problems every day. There is never a dull moment.
• Our startup culture means everyone’s opinion matters. You can have a significant impact.
• Our rapid growth means there are many opportunities for advancement.
• The chance to do something meaningful. Proton products protect dissidents, journalists, and activists. Our work saves lives.
• Be part of something bigger. Millions of people and businesses around the world have embraced our idea of an Internet where privacy and security are the default. Join the privacy revolution that is changing the world.