Regional hiringpublishedExternal employer
PProton
ProtonCybersecurity

Senior Frontend Engineer

Browser Extensions, Desktop Applications

Location

Paris, France

Work type

Hybrid

Employment

Full Time

Experience

5-8 years

Compensation

Compensation not disclosed

Posted

13h ago

Summary and responsibilities

Role overview

Summary

The Senior Frontend Engineer will develop and implement high-quality user experiences across web, browser extensions, and desktop applications for Proton Pass. This role involves close collaboration with cross-functional teams, conducting code reviews, and developing comprehensive testing strategies to ensure product reliability.

What you will do:

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

  • Collaboration: Work closely with backend, product owners, designers, QA, and other engineers to take initiatives from ideation to completion. Break down large initiatives into smaller milestones to gather stakeholder feedback quickly.

  • 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, including unit tests and end-to-end testing tests, to ensure the reliability of the Proton Pass product.

Job Requirements:

  • Proven front-end expertise with deep technical knowledge of browser internals, extension APIs, and desktop application frameworks.

  • Deep understanding of the Javascript ecosystem.

  • Proficiency with TypeScript or type-safe programming paradigms.

  • Strong understanding of software engineering best practices, Design patterns, CI/CD.

  • A product mindset with a focus on offering the best user experiences.

  • Experience working in a distributed team.

Bonus points for:

  • Experience with modern MV3 browser extension development.

  • Experience with Electron or similar desktop application frameworks.

  • Experience with browser extensions and/or cross-platform web applications.

  • Experience working with service-worker architectures.

  • Experience with WebAssembly and/or Rust.

  • Experience with breaking down product requirements into architecture design and implementation.

  • Experience with event-driven systems.

  • Familiarity with UX, accessibility and localization concerns.

  • Experience with application monitoring strategies.

  • High-level understanding of cryptography concepts such as key exchange and the difference between symmetric and asymmetric encryption.

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.

  • A great Team: Our team is diverse, collaborative, and tight-knit with people coming from all walks of life, including many of the world’s top academic institutions and organizations, such as MIT, Harvard, Stanford, Caltech, Cambridge, and ETH.

  • 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

  • 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.

  • 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.

Updated 13h ago

Candidate fit

Skills and qualifications

Additional skills

Frontend Development • 1+ yrs
Browser Internals • 1+ yrs
Extension APIs • 1+ yrs
Desktop Application Frameworks • 1+ yrs
Javascript Ecosystem • 1+ yrs
TypeScript • 1+ yrs
Type-safe Programming • 1+ yrs
Software Engineering Best Practices • 1+ yrs
Design Patterns • 1+ yrs
CI/CD • 1+ yrs
Product Mindset • 1+ yrs
User Experience (UX) • 1+ yrs
Distributed Team Management • 1+ yrs
MV3 Browser Extension Development • 1+ yrs
Electron • 1+ yrs
Cross-platform Web Applications • 1+ yrs
Service-worker Architectures • 1+ yrs
WebAssembly • 1+ yrs
Rust • 1+ yrs
Event-driven Systems • 1+ yrs
Architecture Design • 1+ yrs
UX • 1+ yrs
Accessibility • 1+ yrs
Localization • 1+ yrs
Application Monitoring Strategies • 1+ yrs
Cryptography Concepts • 1+ yrs
Key Exchange • 1+ yrs
Symmetric Encryption • 1+ yrs
Asymmetric Encryption • 1+ yrs
Unit Testing • 1+ yrs
End-to-End Testing • 1+ yrs
Code Review • 1+ yrs
Collaboration • 1+ yrs

Experience

5-8 years

How this role is positioned

Role classification

Job domains

Software Engineering

Industries

Cybersecurity

Employment

Full Time

Contract duration

Permanent

Hiring type

Direct

Global hiring

Location specific

Offer details

Compensation and benefits

Compensation

Compensation not disclosed

VisibilityShared on listing
CurrencyUSD
PeriodYearly

Benefits and perks

Stock Options / ESOP
Flexible Working Hours
Learning & Development Budget

Location, schedule, and role shape

Work setup

Work conditions

Primary locationParis, France
Work typeHybrid
Global hiringNo

Bandwidth profile

peopleMedium7/10
physicalLow2/10
cognitiveHigh8/10
executionHigh8/10
creativityMedium7/10
uncertaintyMedium6/10
communicationMedium7/10

Context on the employer

Company snapshot

Company

Proton

Team size

Growing team

Location

Paris, France

Proton, founded in 2014 by CERN scientists, builds privacy-focused internet tools like Proton Mail, VPN, Drive, Pass, and Calendar. They are profitable, independent, and hire top talent globally, focusing on meaningful work and impact.

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Senior Frontend Engineer

Paris, FranceFull Time