About the role
<p><strong>Join Proton and build a better internet where privacy is the default</strong></p> <p class="Lexical__paragraph">Proton was founded in 2014 by scientists from CERN on a simple truth: <strong><strong class="Lexical__textBold">privacy is a fundamental human right</strong></strong>. Since then, we’ve built the world’s largest encrypted email service (Proton Mail) and expanded into Proton VPN, Proton Drive, Proton Pass, and Proton Calendar—tools used by millions globally to protect their freedom, fight censorship, and keep their data safe. In some situations, Proton has literally helped save lives!</p> <p class="Lexical__paragraph">We are profitable, independent (no VC control), and selectively hire from the top ~1% of applicants. Our 500+ team members across 50+ countries come from leading organizations and elite academic backgrounds. We move fast, keep hierarchy light, and prioritize impact over optics. If you want to do meaningful work with exceptionally high-caliber people, this is it.&nbsp;Join us and do work you can truly be proud of.&nbsp;Check our&nbsp;open-source&nbsp;projects&nbsp;<a class="Lexical__link" href="https://proton.me/community/open-source">here</a>!</p> <p><strong>About the role:</strong></p> <p data-renderer-start-pos="17" data-local-id="76ff49c0d06c">The MSA team (Mail Delivery, Spam, and Anti-Abuse) is a multidisciplinary group founded in 2019 to solve complex security challenges across the Proton ecosystem. We build sophisticated systems from scratch that combine human intelligence and machine learning to make tens of millions of real-time or asynchronous decisions daily. Our focus areas include:</p> <ol class="ak-ol" data-local-id="b1fa507c-e4ff-4dee-a85b-89506c005419" data-indent-level="1"> <li> <p data-renderer-start-pos="375" data-local-id="75dac7c5f179"><strong data-renderer-mark="true">Mail delivery and spam prevention</strong></p> </li> <li> <p data-renderer-start-pos="412" data-local-id="36e428cad0db"><strong data-renderer-mark="true">Abuse detection </strong></p> </li> <li> <p data-renderer-start-pos="432" data-local-id="5b4aec57f48f"><strong data-renderer-mark="true">Account security</strong></p> </li> <li> <p data-renderer-start-pos="452" data-local-id="dc8f1f324116"><strong data-renderer-mark="true">Site reliability and resilience</strong></p> </li> </ol> <p data-renderer-start-pos="487" data-local-id="5359b2dd7eba">Over the past few years, our custom systems have:</p&