Frontend Engineer (Inbox Web) in London

Join Proton and build a better internet where privacy is the default

At Proton, we believe that privacy is a fundamental human right and the cornerstone of democracy. Since our inception in 2014, founded by a team of scientists from CERN, we have dedicated ourselves to providing free and open-source technology to millions worldwide, ensuring access to privacy, security, and freedom online.

Our journey began with Proton Mail, the largest secure email service globally, and has since expanded to include Proton VPN, Proton Calendar, Proton Drive, and Proton Pass. These tools empower individuals and organizations to take control of their personal data, break away from Big Tech’s invasive practices, and defeat censorship. Our work impacts hundreds of millions of lives, from activists on the front lines defending freedom to leaders in governments protecting sensitive information. In some cases, Proton’s services have even been instrumental in saving lives by enabling secure and private communications in high-risk situations.

Proton today supports over 100 million user accounts with a growing team of over 500 people from over 50 different countries, from the world's top companies and universities. We value intelligence, learning potential, and ambition in our hiring process. Adaptability is key as we navigate uncharted territories and redefine how business is conducted online. We believe smaller teams of exceptional talent will always prevail over larger teams with lower talent density. Proton has become profitable and reached scale without relying upon VC funding, largely due to superior talent that allows us to do things faster, more creatively, and more efficiently.

We have a global mindset and big ambitions but remain a start-up at heart. We value empowerment and flexibility and keep our structure flat to keep moving fast and avoid unnecessary politics. Tired of blending into the crowd? Join us and do work you can truly be proud of. Check our social media pages to learn more about us: Twitter, Reddit, Instagram.

The Team:

As a Frontend Engineer on the Inbox team, you will play a crucial role in developing Proton's most vital services, including Mail and Calendar. We expect you to be customer-centric, continuously learning, passionate about technology and usability. You are an adept at turning technical complexities into seamless user experiences. Effective teamwork, collaboration with Product, Design, APIs, and your team, and data-driven decision-making are essential aspects of this role.

Key responsibilities:

• Take end-to-end ownership of mobile application development projects: you'll be comfortable with scoping projects, walking back from deadlines and being able to discern the important from the superfluous


• Foster a culture of innovation by exploring new technologies, methodologies and approaches to web development – we tackle complex engineering challenges with creativity and ingenuity


• Design for scalability, considering factors such as data caching, network bandwidth and server load


• Implement solutions to monitor and alert the team regarding the state of Inbox web clients


• Prioritize customer satisfaction by maintaining a customer-centric mindset throughout the development process, continuously seeking feedback and iterating to improve the user experience

Tech Stack and Tools:

Javascript, TypeScript, React, Symfony, Rust

• Every Proton clients codebase are open source, Check it out here.


• Encryption brings unique challenges to front-end development. A trivial search functionality becomes much more interesting to implement when the email body is fully encrypted.

What you will do

• Develop new features: Developing, deploying and supporting high-quality user experiences, including feature development and implementation.


• Drive adoption and user retention: you will contribute to the user onboarding and delivering a delightful experience to retain


• Collaboration: Work closely with backend, product owners, designers, QA, and other engineers to take initiatives from ideation to completion.


• Code review and optimization: Conduct code reviews and provide constructive feedback to ensure code quality, maintainability, and performance optimization.


• Testing: Develop and implement comprehensive testing strategies, on all test layers to ensure reliability and future ease of development.

Job requirements

While we prefer candidates who cover the entire skillset, don't hesitate to apply if you're not an exact match, as we're willing to help you grow in certain areas.

• Extensive experience of professional software development using JavaScript or TypeScript.


• Experience with React or 2+ similar frameworks, developing performant and reusable components.


• Experience contributing to an API codebase, bonus points if in PHP


• Experience writing tests at scale


• Familiarity with other best practices for ensuring code quality, including CI/CD.

Nice to have:

• Experience with monitoring and observability tools


• Experience working in a distributed team


• Awareness of common security issues in client-side development, such as those in the OWASP top ten, and how to mitigate them


• Familiarity with UX, accessibility, internationalization, and localization concerns and solutions

Even if you don’t meet all the requirements listed above, but feel you could still be a great fit, please still apply.

What We Offer

• Office First: Collaboration is easier and more effective in person, which is why we have offices in Geneva, Zurich, Prague, Barcelona, Paris, London, Vilnius, Skopje, and Taipei. You can also enjoy working from home up to 30% of the time, while enjoying great company during our three core days in the office.


• Technology: We provide all the devices and software you need to excel in your role, ensuring you have the best tools at your disposal to achieve your goals.


• Food: Lunch and snacks are provided by Proton every day at our offices.


• Transport: We will always support our employees with transport costs through subsidizing public transport, bike allowances, or parking spaces based on your office location.


• Stock Options: At Proton, we are all owners of the company and you get stock options when you join us.


• Flexible Working: You can define your own working hours as long as it works with team meetings.


• Learning and Development: We are committed to your professional growth. Proton offers various learning opportunities, including training programs, conferences and events, and continual learning.


• Employee Benefits: Comprehensive health insurance plans, competitive retirement savings options, generous vacation and leave policies, and wellness programs.


• Work that Matters: Proton is a community-first organization, started with the support of a crowdfunding campaign and built with community input. To this day, Proton’s only source of revenue is user subscriptions. Over 100 million people trust and support Proton, and we put our users and community first in everything we do. Read more about our impact here.

Check our social media to learn more about Proton:

LinkedIn ,Reddit ,X, YouTube

Our Commitment to Diversity and Inclusion

At Proton, we believe diversity drives innovation and strengthens our mission to provide privacy as a default for all. We are committed to fostering an inclusive environment where all individuals, regardless of race, ethnicity, gender, age, sexual orientation, physical ability, or socio-economic background, feel valued and empowered. We strive to create equal opportunities, promote open dialogue, and support continuous learning to ensure every voice is heard and respected.

If you need any extra support or reasonable adjustments during the hiring process, please let your talent partner know.

Candidate Privacy Notice

When you apply for a position, refer a candidate, or are considered for a role at Proton Technologies AG (Proton, we, us, or our), your information is stored in Greenhouse, in accordance with their Service Privacy Policy. This information is used to evaluate your suitability for the posted position. We also retain this information for consideration for future roles that you may apply for or that we believe may align with your background and skills.

If we no longer have a legitimate business need to process your information, we will either delete or anonymize it. Should you have any inquiries about how we use or manage your information, or if you wish to access, correct, or delete your data, please contact our privacy team at careers@proton.ch.

Proton does not accept unsolicited resumes from any sources other than directly from candidates. We will not pay a fee for any placement resulting from an unsolicited offer, even if the candidate is subsequently hired by Proton.

To learn more about our privacy policy, please visit our privacy policy page.

#LinkedIn-Onsite