Junior Software Developer jobs in United Kingdom

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 is a profitable company that does not rely upon VC funding, supporting 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.

Hiring at Proton is highly selective, with less than 1% of candidates hired. We believe smaller teams of exceptional talent will always prevail over larger teams with lower talent density. You will have the opportunity work with many of the world's top minds in their fields, ranging from former international math and science olympiad winners to chess champions.

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 open-source projects here !

Our business unit, Inbox, is a cross-functional team of about 60 engineers, product managers, designers and data analysts driving the development of Proton Mail, the company’s flagship product, and Proton Calendar. Our mission is to create an end-to-end encrypted solution with a better user experience than any other productivity products on the market. While it is not always an easy journey, it is one that offers the chance to create meaningful impact and drive lasting change that we are fully committed to.

The Inbox Desktop team is responsible for developing desktop clients of Inbox, specifically the Proton Mail Desktop App, Proton Mail Bridge, and the Export tool. We are in the process of rebuilding our client applications on a new, innovative technology stack centred around cross-platform Rust code. We are looking for a Senior Software Engineer to take the technical ownership of the Proton Mail Desktop App on Windows and Linux platforms.

Currently, we use many languages and frameworks in the team like Golang, C++, Qt, JS, TypeScript, React, or Electron. We use standard tools for communication and work organization (Git, GitLab, GitHub, GitLab CI, Jira, Confluence). Our backend runs on premise in Proton’s data centers, and all our client-code is open source and GPL3.

As a Senior Software Engineer in the Inbox Desktop team, you will play a crucial role in driving the development of one of Proton's most vital desktop offerings, the Proton Mail Desktop App. You will be customer‑centric, a continuous learner, passionate about technology and usability, and adept at turning technical complexities into seamless user experiences. Effective teamwork, data‑driven decision making, and collaboration with Product, Design, and other teams are essential aspects of this role.

In the Inbox organization, we believe that a psychologically safe environment is critical to foster innovation, collaboration, and growth. We are rooted in science, and according to both academic research and empirical evidence, teams that feel safe to take risks and express their ideas are more likely to be innovative and perform better. You will help create such an environment across the entire organization.

• Research: Assess new technologies and support cross‑team and cross‑business unit technical decision making.
• Work breakdown: Transform product specifications into technical requirements and lead your team to successful implementation.
• Product development: Ensure high‑quality user experiences within our product portfolio by implementing, deploying, and maintaining existing and new features.
• Scalability: Enhance software development lifecycle, tools, and processes to improve developer experience and ensure our solutions are scalable.
• Coding: Write clear, concise, and testable code to maintain and elevate the quality of our codebase.
• Project management: Manage the scoping, planning, and execution of new features, technical initiatives, and greenfield projects.
• Mentoring: Foster a culture of learning, creativity, and accountability through mentorship and team development, and model quality assurance and performance optimization.

• Experience: Significant, relevant professional software development experience with Rust, or with a very strong background in modern C++ and reasonably complex Rust pet projects.
• Desktop software development: Experience developing high quality, fast, Windows and Linux cross‑platform desktop applications. Familiarity with different native and cross‑platform desktop UI frameworks (e.g. Avalonia UI, Qt, Electron, etc.). Experience working both on user interface and on business logic.
• Product mindset: A product mindset focusing on outstanding user experience in a successful business environment. Familiarity with key business and product performance metrics.
• Engineering leadership: Ability to make architectural decisions and contribute to strategic planning and product directions. Experience developing scalable engineering solutions. Able to write effective engineering documents.
• Collaborative Skills: Proven ability to work collaboratively in a team environment, excellent written communication skills, and experience working in a distributed team.
• Problem‑solving: Strong problem‑solving skills and the ability to troubleshoot customer issues remotely while protecting our user’s privacy. Know proactive solutions to implement to prepare for such scenarios.
• Security focus: Understanding of secure coding practices and a commitment to maintaining high levels of security and privacy.
• Bachelor's or Master's degree: In Computer Science, Software Engineering, or a related field.

• Experience with macOS or mobile cross‑platform development.
• Familiarity with using unidirectional data‑flow (a.k.a. Elm‑like) frameworks.
• Experience with Grafana, Metabase or other monitoring platforms.
• Experience in B2B, preferably in online privacy and/or productivity contexts.

• Office First: Collaboration is easier and more effective in person. 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. All of our teams are based in Europe (same timezone ± 1 hour).
• Technology: You can work on introducing new technologies, both for green field projects and for existing systems. 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 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.

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.

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 .