Ilir Sela started Slice with the belief that local pizzerias deserve all of the advantages of major franchises without compromising their independence. Starting with his family’s pizzerias, we now empower over tens of thousands of restaurants with the technology, services, and collective power that owners need to better serve their digitally minded customers and build lasting businesses. We’re growing and adding more talent to help fulfil this valuable mission. That’s where you come in.

This position is open to applicants across all of the UK on a remote basis, with the physical office located in Belfast, Northern Ireland.

The Role

By applying your Mobile experience, and software development skills, you will build high quality and intuitive experiences for customer-facing and business-facing apps. You will collaborate with other developers to build scalable solutions that make it easy to build high quality products, and you will work alongside designers and other stakeholders to build exciting new features and refine existing experiences. You will integrate with our custom built in-shop embedded projects. Knowledge of more than one mobile stack as well as an interest in embedded systems is a bonus. 

For this role, we are focusing on hiring at the Senior level, which requires broad professional mobile development experience and a strong track record of leading complex initiatives and delivering broad impact. We recognise that job titles and responsibilities vary across companies; throughout our interview process we assess each candidate’s experience, technical depth and overall impact to ensure alignment with the appropriate level at Slice.

The Team

You will be part of our Devices development team that is responsible for all of our customer-facing and business-facing mobile and embedded products. Think pizza ordering apps, Point-of-sale and Kiosk’s to name a few. We believe that consolidating our skills on platform-specific teams leads to a better development environment where you can collaborate, learn from and grow alongside other device experts. Our team brings together talented developers from across the US, UK, and Eastern Europe, each contributing unique perspectives and expertise to drive success.

The Winning Recipe

We’re looking for creative, entrepreneurial developers who are excited to build world-class products for small businesses and their customers. 

The core competencies this role calls for:

• Proven experience developing iOS apps with Swift, SwiftUI, Combine and Core Data.
• Hands-on experience designing, developing and maintaining Android applications with Kotlin & Jetpack Compose is required.
• Technical leadership and strategic impact: able to guide complex projects end-to-end, influence architecture decisions and lead peers.
• Experience with Python, particularly in developing web services, is a plus.
• Embedded systems experience is highly desirable.
• Able to clearly express opinions on product design, while respecting the thoughts and opinions of their peers.
• Adaptable, proactive and results-oriented, capable of delivering solutions efficiently and meeting tight deadlines.
• Proven ability to communicate and collaborate effectively with engineers across all platforms and non-engineering stakeholders alike.
• Comfortable working remotely and collaborating asynchronously with teammates in different timezones and from different backgrounds.

The Extras

Working at Slice comes with a comprehensive set of benefits, but here are some of the unexpected highlights:

• Access to healthcare plans
• Flexible working hours
• Generous time off policies
• Employee wellbeing allowance
• Market leading maternity and paternity schemes

The Hiring Process

Here’s what you can expect from our hiring process if your candidacy progresses smoothly. We move quickly and strive for a fast turnaround from the final interview to the offer.

• Application
• 30-minute introductory meeting
• 90 minute Live Coding Interview & 60 minute Technical Interview
• 30-minute Hiring Manager meeting
• Offer!

Pizza brings people together. Slice is no different. We’re an Equal Opportunity Employer and embrace a diversity of backgrounds, cultures, and perspectives. We do not discriminate on the basis of race, colour, gender, sexual orientation, gender identity or expression, religion, disability, national origin, protected veteran status, age, or any other status protected by applicable national, federal, state, or local law. We are also proud members of the Diversity Mark NI initiative as a Bronze Member.

Privacy Notice Statement of Acknowledgment

When you apply for a job on this site, the personal data contained in your application will be collected by Slice. Slice is keeping your data safe and secure. Once we have received your personal data, we put in place reasonable and appropriate measures and controls to prevent any accidental or unlawful destruction, loss, alteration, or unauthorised access. If selected, we will process your personal data for hiring /employment processes, as well as our legal obligations.

If you are not selected for the job position and you have given consent on the question below (by selecting "Give consent") we will store and process your personal data and submitted documents (CV) to consider eligibility for employment up to 365 days (one year). You have the right to withdraw your previously given consent for storing your personal data and CV in the Slice database considering eligibility for employment for a year. You have the right to withdraw your consent at any time.

For additional information and / or exercise of your rights to the protection of personal data, you can contact our Data Protection Officer, e-mail: privacy@slice.com

About Proton

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

Proton was founded in 2014 by scientists from CERN on a simple truth: privacy is a fundamental human right. 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!

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. Join us and do work you can truly be proud of. Check our open-source projects here!

The team:

We're a tight-knit, passionate Android engineering team building privacy-first apps that are trusted by millions of people around the world — and yes, our code is open source, so your work is truly out there making a difference. We move fast, skip the bureaucracy, and genuinely care about what we ship. Whether you're deep in Espresso tests or debating architecture over lunch, you'll be surrounded by people who are as excited about quality as you are. If you love Android, hate flaky tests, and want your work to actually matter — you'll fit right in.

Tech Stack and Tools:

Kotlin, Java, Espresso, UI Automator, Maestro

What you will do:

• Design, develop, and maintain automated test frameworks and pipelines for Proton's Android applications

• Write and execute UI, functional, integration, and end-to-end test suites using modern Android testing tools and best practices

• Work hand-in-hand with Android developers to define testability requirements and embed automated tests into CI/CD workflows

• Hunt down bugs, document them clearly, and collaborate with the team to get them fixed fast

• Perform exploratory and risk-based testing with a sharp eye on privacy, data integrity, and security behavior

• Own and evolve the Android test infrastructure, including emulator farms, device labs, and test environment configurations

• Dig into test results, spot patterns, and turn findings into actionable improvements that raise the quality bar

• Champion QA best practices across the team and help shape how we think about quality at every stage of development

• Review test code with the same rigor as production code — maintainability and scalability matter here

• Keep up with the Android ecosystem, new testing frameworks, and open-source tooling so we're always ahead of the curve

What we are looking for:

• 3–5 years of hands-on experience in Android test automation, ideally on consumer-facing apps with a large user base

• Strong proficiency in Kotlin and/or Java, with solid experience writing clean, maintainable test code

• Proven experience with Android testing frameworks such as Espresso, UI Automator, or Maestro

• Good understanding of CI/CD pipelines and experience integrating Android tests with tools like GitLab CI, GitHub Actions, or similar

• Familiarity with Android emulators, physical device testing, and cloud-based device farms (e.g., Firebase Test Lab)

• Comfortable navigating Android Studio, ADB, and the broader Android development toolchain

• Experience with version control using Git, and a natural fit in an open-source collaborative workflow

• A good nose for security and privacy issues — understanding of privacy-by-design is a real plus

• Ability to read and understand application source code to sharpen test coverage and catch edge cases early

• Sharp analytical mindset with a structured, detail-oriented approach — you don't let things slip through the cracks

• Great communicator who thrives in a remote-friendly, internationally distributed team

• Genuine enthusiasm for open-source software, Android, and building technology that protects people's privacy

What We Offer:

• Work that Matters: millions of people trust Proton with their privacy. We answer only to our users — not advertisers, not investors with conflicting agendas, not governments. The work you do here is real, and the impact is measurable. (read more about our impact here)

• Stock Options: at Proton, we all have the opportunity to be owners of the company. From day one, you have a real stake in what we're building. When Proton wins, you win.

• Technology: you'll get the right hardware and the right software you need to do your best work.

• Learning & Development: we invest in your growth because sharp people make us better. Proton is one of the fastest ways to accelerate your career because you'll be thrown into real challenges, with real ownership, from day one.

• Employee Benefits: your wellbeing isn't an afterthought. We offer strong health coverage, solid retirement options, generous leave, and wellness support so you can bring your best self to work every day

• In-Person Collaboration: Amazing things happen when passionate, smart, and purposeful people get together in the same room. With offices across Geneva, Zürich, Barcelona, London and more, you'll spend most of your time collaborating face-to-face with people who genuinely care about what they're building

• Food: Lunch and snacks are on us every day in our offices so you can focus on the work and not on what's for lunch.

• Transport: getting to the office shouldn't cost you. We cover public transport, bike allowances, or parking, whichever works for you.

• Flexible Working: you own your schedule. Set hours that work for you and your team — because outcomes matter more than when the clock says you started.

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.

Salary range (Vilnius) - 48.800 - 54.200 EUR gross annual 

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