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 to 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!

The team:

Proton VPN enables millions of people to connect securely and privately, even in places where the internet is restricted or unreliable. Delivering that experience means our service must perform flawlessly under highly variable, real-world conditions.

We are looking for a Senior Performance Engineer to lead our efforts in making Proton VPN the fastest, most resilient, and most reliable VPN service in the world.

You will define and drive the measurement, analysis, and optimization of Proton VPN’s end-to-end performance, across clients, platforms, and global infrastructure. You’ll help ensure that every connection is fast, stable, and private, regardless of where the user is or what network they’re on.

What you will do: 

• Design and own Proton VPN’s performance framework, defining metrics and KPIs that reflect the real-world experience of users (time-to-connect, throughput, latency, stability, reconnection rates, etc.).
• Develop distributed testing systems that simulate real network conditions, including low bandwidth, packet loss, and high-latency scenarios.
• Continuously measure and analyze performance across platforms (desktop, mobile, backend) and regions to identify bottlenecks and regressions.
• Collaborate with backend, R&D, and client teams to optimize protocol handling, connection setup, routing, and encryption performance.
• Create dashboards, reports, and automated alerts to track global performance health.
• Contribute to the design of resilient connectivity strategies that adapt dynamically to variable network conditions.
• Serve as the performance champion within the engineering organization, mentoring others and driving a data-driven performance culture.

Job requirements: 

Technical Skills

• 5+ years of experience in performance engineering or systems QA, ideally in networking, VPNs, or distributed systems.
• Knowledge of network protocols (TCP/IP, UDP, TLS, WireGuard, debugging, manipulating, and performance profiling tools.
• Proven ability to analyze latency, throughput, and stability metrics across multiple layers (client, OS, transport, application).
• Proficiency in Python (or similar scripting language)
• Familiarity with network emulation and simulation tools (e.g., tc/netem, iperf, IPTables/nfTables…).
• Experience with monitoring and observability stacks (Grafana, Prometheus, Loki) and CI/CD pipelines.
• Cross-platform experience with Linux, macOS, Windows, Android, and iOS preferred.

Bonus points for: 

• Experience with Rust/C/C++/System development

Soft Skills

• Analytical and methodical, yet creative in solving complex performance problems.
• Comfortable working with uncertainty and non-deterministic conditions.
• Collaborative mindset, able to work across client, infrastructure, and data teams.
• Strong communication and documentation skills in English.

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.

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.

#LI-Onsite

Who we are

The role

At Helsing we deliver AI-based capabilities and the enabling foundation that allow machines to perceive and assist human decision-making. You will have the unique opportunity to shape AI capabilities in one of the most challenging sectors, where high generalisation capabilities need to be paired with hardware constraints and real-world robustness.

You will be part of a team pushing the boundaries of autonomous robotics through reinforcement learning. Your work will focus on designing, training and deploying RL-based controllers for robots operating in complex, unstructured, and dynamic real-world environments — where classical control approaches fall short. This includes enabling robots to perceive and understand their surroundings by fusing rich sensory inputs, including vision, to inform robust and adaptive control. You will own the full pipeline from simulation to deployment, ensuring that learned policies are robust, efficient, and ready for real-world operation under tight hardware constraints.

You should apply if you

• Hold an MSc or PhD in Robotics, Machine Learning, Control Engineering, or a closely related field, with a strong focus on reinforcement learning and robot control.

• Have hands-on experience training and deploying RL-based controllers on real robotic hardware, not just in simulation — you have seen your policies fall, iterate, and ultimately succeed on a physical system.

• Are deeply familiar with modern RL techniques for continuous control, including but not limited to: model-free methods (PPO, SAC, TD3), model-based RL, hierarchical RL, sim-to-real transfer strategies, domain randomisation, and curriculum learning.

• Have a solid understanding of robot dynamics, kinematics, and classical control theory (e.g. PID, model predictive control, trajectory optimisation), and know when and how to combine them with learned approaches.

• Are proficient in building and working with physics-based simulators (e.g. MuJoCo, Isaac Gym/Isaac Lab, PyBullet, Gazebo) for training and validating RL policies.

• Possess solid software engineering skills, writing clean and well-structured code in Python and/or languages like Rust or modern C++, and have experience deploying AI software to production including testing, QA, and monitoring.

• Have excellent communication skills and the ability to report and present research findings clearly and efficiently, both internally and externally.

• Are passionate about keeping up to date with current research and enjoy re-implementing and extending state-of-the-art papers.

Note: We operate at an intersection where women, as well as other minority groups, are systematically under-represented. We encourage you to apply even if you don’t meet all the listed qualifications; ability and impact cannot be summarised in a few bullet points.

Nice to have

• PhD in Robotics, Reinforcement Learning, Control Engineering, or related fields, with publications in top-tier venues (e.g. CoRL, ICRA, NeurIPS, ICLR, IROS, RSS).

• Experience developing controllers for highly dynamic robotic systems operating under complex contact interactions and demanding environmental conditions.

• Experience with vision-based perception for robotics control, such as depth estimation, visual odometry, or visuomotor policy learning.

• Familiarity with low-level motor control interfaces and real-time embedded systems constraints.

• Experience with online adaptation and meta-learning techniques to enable robots to adapt to changing environmental conditions

• Experience with sensor fusion (IMU, proprioception, exteroception, vision) to inform and enhance learned control policies.

Join Helsing and work with world-leading experts in their fields

• Helsing’s work is important. You’ll be directly contributing to the protection of democratic countries while balancing both ethical and geopolitical concerns. 

• The work is unique. We operate in a domain that has highly unusual technical requirements and constraints, and where robustness, safety, and ethical considerations are vital. You will face unique Engineering and AI challenges that make a meaningful impact in the world. 

• Our work frequently takes us right up to the state of the art in technical innovation, be it reinforcement learning, distributed systems, generative AI, or deployment infrastructure. The defence industry is entering the most exciting phase of the technological development curve. Advances in our field of world are not incremental: Helsing is part of, and often leading, historic leaps forward. 

• In our domain, success is a matter of order-of-magnitude improvements and novel capabilities. This means we take bets, aim high, and focus on big opportunities. Despite being a relatively young company, Helsing has already been selected for multiple significant government contracts.  

• We actively encourage healthy, proactive, and diverse debate internally about what we do and how we choose to do it. Teams and individual engineers are trusted (and encouraged) to practise responsible autonomy and critical thinking, and to focus on outcomes, not conformity. At Helsing you will have a say in how we (and you!) work, the opportunity to engage on what does and doesn’t work, and to take ownership of aspects of our culture that you care deeply about. 

What we offer

• Competitive salary and VSOP options

• Relocation support: up to €2,500 and 4 weeks temporary accommodation

• Learning: €500/£450 yearly allowance

• Health & wellness: gym membership and mental health support (Nilo.health)

• Social: regular company events and monthly social allowances

• Enhanced parental leave: 22 weeks fully paid for primary caregivers & 6 weeks for secondary caregivers

• Family support: 5 days of paid family emergency leave, 100% remote work option during pregnancy and phased return to work

These are the core benefits across all locations, there may be additional benefits in certain locations.

Helsing is an equal opportunities employer. We are committed to equal employment opportunity regardless of race, religion, sexual orientation, age, marital status, disability or gender identity. Please do not submit personal data revealing racial or ethnic origin, political opinions, religious or philosophical beliefs, trade union membership, data concerning your health, or data concerning your sexual orientation.

Responsibilities

We are looking for a Senior Rust Software Developer. In this role, you will also be responsible to:

• Building new products inside the company.

• Develop new code with Rust, and deal with existing Go/Ruby code

• Create PoC in the new areas and drive them to production or drop them away.

Requirements

Qualifications / Experience / Technical Skills

• Strong experience writing, shipping, and maintaining Rust code (2+ years), and experience with other languages (Ruby, Python, Go, JS, Java, etc.)
  
  
• Knowledge of basic data structures and algorithms, multiprocessing, memory management.
  
  
• Experience developing high-performance asynchronous applications with Rust (preferably tokio).
  
  
• Good understanding of network protocols and stacks.
  
  
• Good understanding of DB technologies: classic databases and modern no-SQL.
  
  
• Basic knowledge of DevOps practices and tools
  
  
• Understanding of Linux environment
  
  
• Golang/Ruby knowledge is a plus
  
  
• Experience working with WASM is a plus
  
  
• Open Source contributions is a plus

Soft Skills / Personal Characteristics

• Readiness to work remotely with teams distributed across the world and timezones
  
  
• Spoken English (at the level enough to pass the technical interview and later work with colleagues)
  
  
• Being a result-oriented problem solver.
  
  
• Prefers coming up with proposals in problematic areas, rather than being passive.
  
  
• Being open to new technologies and switching between projects.
  
  
• Readiness to travel for business

(REQ ID: 2682)

Responsibilities

We are looking for a Senior Rust Software Developer. In this role, you will also be responsible to:

• Building new products inside the company.

• Develop new code with Rust, and deal with existing Go/Ruby code

• Create PoC in the new areas and drive them to production or drop them away.

Requirements

Qualifications / Experience / Technical Skills

• Strong experience writing, shipping, and maintaining Rust code (2+ years), and experience with other languages (Ruby, Python, Go, JS, Java, etc.)
  
  
• Knowledge of basic data structures and algorithms, multiprocessing, memory management.
  
  
• Experience developing high-performance asynchronous applications with Rust (preferably tokio).
  
  
• Good understanding of network protocols and stacks.
  
  
• Good understanding of DB technologies: classic databases and modern no-SQL.
  
  
• Basic knowledge of DevOps practices and tools
  
  
• Understanding of Linux environment
  
  
• Golang/Ruby knowledge is a plus
  
  
• Experience working with WASM is a plus
  
  
• Open Source contributions is a plus

Soft Skills / Personal Characteristics

• Readiness to work remotely with teams distributed across the world and timezones
  
  
• Spoken English (at the level enough to pass the technical interview and later work with colleagues)
  
  
• Being a result-oriented problem solver.
  
  
• Prefers coming up with proposals in problematic areas, rather than being passive.
  
  
• Being open to new technologies and switching between projects.
  
  
• Readiness to travel for business

(REQ ID: 2682)

Responsibilities

We are looking for a Senior Rust Software Developer. In this role, you will also be responsible to:

• Building new products inside the company.

• Develop new code with Rust, and deal with existing Go/Ruby code

• Create PoC in the new areas and drive them to production or drop them away.

Requirements

Qualifications / Experience / Technical Skills

• Strong experience writing, shipping, and maintaining Rust code (2+ years), and experience with other languages (Ruby, Python, Go, JS, Java, etc.)
  
  
• Knowledge of basic data structures and algorithms, multiprocessing, memory management.
  
  
• Experience developing high-performance asynchronous applications with Rust (preferably tokio).
  
  
• Good understanding of network protocols and stacks.
  
  
• Good understanding of DB technologies: classic databases and modern no-SQL.
  
  
• Basic knowledge of DevOps practices and tools
  
  
• Understanding of Linux environment
  
  
• Golang/Ruby knowledge is a plus
  
  
• Experience working with WASM is a plus
  
  
• Open Source contributions is a plus

Soft Skills / Personal Characteristics

• Readiness to work remotely with teams distributed across the world and timezones
  
  
• Spoken English (at the level enough to pass the technical interview and later work with colleagues)
  
  
• Being a result-oriented problem solver.
  
  
• Prefers coming up with proposals in problematic areas, rather than being passive.
  
  
• Being open to new technologies and switching between projects.
  
  
• Readiness to travel for business

(REQ ID: 2682)

Responsibilities

We are looking for a Senior Rust Software Developer. In this role, you will also be responsible to:

• Building new products inside the company.

• Develop new code with Rust, and deal with existing Go/Ruby code

• Create PoC in the new areas and drive them to production or drop them away.

Requirements

Qualifications / Experience / Technical Skills

• Strong experience writing, shipping, and maintaining Rust code (2+ years), and experience with other languages (Ruby, Python, Go, JS, Java, etc.)
  
  
• Knowledge of basic data structures and algorithms, multiprocessing, memory management.
  
  
• Experience developing high-performance asynchronous applications with Rust (preferably tokio).
  
  
• Good understanding of network protocols and stacks.
  
  
• Good understanding of DB technologies: classic databases and modern no-SQL.
  
  
• Basic knowledge of DevOps practices and tools
  
  
• Understanding of Linux environment
  
  
• Golang/Ruby knowledge is a plus
  
  
• Experience working with WASM is a plus
  
  
• Open Source contributions is a plus

Soft Skills / Personal Characteristics

• Readiness to work remotely with teams distributed across the world and timezones
  
  
• Spoken English (at the level enough to pass the technical interview and later work with colleagues)
  
  
• Being a result-oriented problem solver.
  
  
• Prefers coming up with proposals in problematic areas, rather than being passive.
  
  
• Being open to new technologies and switching between projects.
  
  
• Readiness to travel for business

(REQ ID: 2682)

We are looking for a Distributed Systems Engineer with experience in building high-performing, scalable, enterprise-grade applications. You will be responsible for building API interfaces (for customers, UI team etc). You will be responsible for building a high performance queuing/storage engine. You will collaborate with UI, connectivity and DevOps teams to come up with elegant solutions to complex problems. You will work in a polyglot environment where you can learn new languages and technologies whilst working with an enthusiastic team.

Responsibilities

• Responsibilities include designing and developing high-volume, low-latency applications for mission-critical systems and delivering high-availability and performance

• Contribute in all phases of the development lifecycle

• Write well designed, testable, efficient code

• Evaluate and propose improvements to existing system

Requirements

• 5+ years of industry experience

• Experience building and shipping large-scale, reliable, highly distributed systems

• Systems-level programming experience, especially in C, Go, Rust

• Expertise in L2, L3, and/or L4 networking protocols

• Good understanding of Linux networking and security

• Experience building on top of Linux kernel networking primitives – netfilter, nftables, eBPF, tc, network namespaces, etc

• Experience with large-scale distributed data pipelines, from data structuring to efficient querying to data analysis

• Experience of working with public cloud infrastructure providers (AWS/Azure/Google Cloud)

• Understanding of Kubernetes concepts

• Excellent debugging and optimization skills

• Understanding at the protocol level, including the differences between what the specs say, and what actually happens on the Internet

• Contributions to open source projects is a plus

• Excited by the idea of optimizing complex solutions to general problems

• Attention to detail and ability to solve complex customer problems

• Own solutions end-to-end and driving the design, development, and deployment process

• Able to work across teams and level common, sustainable solutions

We are looking for a Distributed Systems Engineer with experience in building high-performing, scalable, enterprise-grade applications. You will be responsible for building API interfaces (for customers, UI team etc). You will be responsible for building a high performance queuing/storage engine. You will collaborate with UI, connectivity and DevOps teams to come up with elegant solutions to complex problems. You will work in a polyglot environment where you can learn new languages and technologies whilst working with an enthusiastic team.

Responsibilities

• Responsibilities include designing and developing high-volume, low-latency applications for mission-critical systems and delivering high-availability and performance

• Contribute in all phases of the development lifecycle

• Write well designed, testable, efficient code

• Evaluate and propose improvements to existing system

Requirements

• 5+ years of industry experience

• Experience building and shipping large-scale, reliable, highly distributed systems

• Systems-level programming experience, especially in C, Go, Rust

• Expertise in L2, L3, and/or L4 networking protocols

• Good understanding of Linux networking and security

• Experience building on top of Linux kernel networking primitives – netfilter, nftables, eBPF, tc, network namespaces, etc

• Experience with large-scale distributed data pipelines, from data structuring to efficient querying to data analysis

• Experience of working with public cloud infrastructure providers (AWS/Azure/Google Cloud)

• Understanding of Kubernetes concepts

• Excellent debugging and optimization skills

• Understanding at the protocol level, including the differences between what the specs say, and what actually happens on the Internet

• Contributions to open source projects is a plus

• Excited by the idea of optimizing complex solutions to general problems

• Attention to detail and ability to solve complex customer problems

• Own solutions end-to-end and driving the design, development, and deployment process

• Able to work across teams and level common, sustainable solutions

We are looking for a Distributed Systems Engineer with experience in building high-performing, scalable, enterprise-grade applications. You will be responsible for building API interfaces (for customers, UI team etc). You will be responsible for building a high performance queuing/storage engine. You will collaborate with UI, connectivity and DevOps teams to come up with elegant solutions to complex problems. You will work in a polyglot environment where you can learn new languages and technologies whilst working with an enthusiastic team.

Responsibilities

• Responsibilities include designing and developing high-volume, low-latency applications for mission-critical systems and delivering high-availability and performance

• Contribute in all phases of the development lifecycle

• Write well designed, testable, efficient code

• Evaluate and propose improvements to existing system

Requirements

• 5+ years of industry experience

• Experience building and shipping large-scale, reliable, highly distributed systems

• Systems-level programming experience, especially in C, Go, Rust

• Expertise in L2, L3, and/or L4 networking protocols

• Good understanding of Linux networking and security

• Experience building on top of Linux kernel networking primitives – netfilter, nftables, eBPF, tc, network namespaces, etc

• Experience with large-scale distributed data pipelines, from data structuring to efficient querying to data analysis

• Experience of working with public cloud infrastructure providers (AWS/Azure/Google Cloud)

• Understanding of Kubernetes concepts

• Excellent debugging and optimization skills

• Understanding at the protocol level, including the differences between what the specs say, and what actually happens on the Internet

• Contributions to open source projects is a plus

• Excited by the idea of optimizing complex solutions to general problems

• Attention to detail and ability to solve complex customer problems

• Own solutions end-to-end and driving the design, development, and deployment process

• Able to work across teams and level common, sustainable solutions

We are looking for a Distributed Systems Engineer with experience in building high-performing, scalable, enterprise-grade applications. You will be responsible for building API interfaces (for customers, UI team etc). You will be responsible for building a high performance queuing/storage engine. You will collaborate with UI, connectivity and DevOps teams to come up with elegant solutions to complex problems. You will work in a polyglot environment where you can learn new languages and technologies whilst working with an enthusiastic team.

Responsibilities

• Responsibilities include designing and developing high-volume, low-latency applications for mission-critical systems and delivering high-availability and performance

• Contribute in all phases of the development lifecycle

• Write well designed, testable, efficient code

• Evaluate and propose improvements to existing system

Requirements

• 5+ years of industry experience

• Experience building and shipping large-scale, reliable, highly distributed systems

• Systems-level programming experience, especially in C, Go, Rust

• Expertise in L2, L3, and/or L4 networking protocols

• Good understanding of Linux networking and security

• Experience building on top of Linux kernel networking primitives – netfilter, nftables, eBPF, tc, network namespaces, etc

• Experience with large-scale distributed data pipelines, from data structuring to efficient querying to data analysis

• Experience of working with public cloud infrastructure providers (AWS/Azure/Google Cloud)

• Understanding of Kubernetes concepts

• Excellent debugging and optimization skills

• Understanding at the protocol level, including the differences between what the specs say, and what actually happens on the Internet

• Contributions to open source projects is a plus

• Excited by the idea of optimizing complex solutions to general problems

• Attention to detail and ability to solve complex customer problems

• Own solutions end-to-end and driving the design, development, and deployment process

• Able to work across teams and level common, sustainable solutions

Responsibilities

We are looking for an exceptional Senior Backend Developer (Ruby) to join our growing Engine team. The Engine team develops and maintains most things related to Workato Recipe runtime. Everything related to recipe execution: DSL, pulling events, processing webhooks, executing jobs. There are various aspects to it: performance, scaling, storage, durability, atomicity, concurrency guarantees, data protection, and encryption. 

 In this role, you will also be responsible to:

• Build/extend/troubleshot/fix complex heterogeneous GOlang and Ruby applications, as well as small self-contained GOlang microservices.

• Improve execution engine of custom third-party code (Ruby DSL, isolation, performance, new features).

• Write well designed, testable, efficient code in Ruby and GOlang.

• Integration of data storage solutions Postgres/S3/DynamoDB/Kafka/ClickHouse etc.

• Contribute in all phases of the development lifecycle.

• Provide code reviews to your teammates.

• Provide technical leadership. Work with other teams on shared projects.

• Evaluate and propose improvements to existing systems.

• Identify bottlenecks and bugs, and devise solutions to these problems.

• Help maintain code quality, organization and automatization.

• We always explore new technologies and work with Rust and Wasm can be foreseen.

Requirements

Qualifications / Experience / Technical Skills

• Strong experience in building scalable distributed backend applications (7+ years).

• Excellent understanding of distributed systems patterns and algorithms.

• Great understanding of all building blocks of large web applications: databases, load balancers, application servers, message brokers, caching, monitoring, etc.

• Excellent understanding of network protocols and stacks.

• Excellent understanding of DB technologies: classic databases and modern no-SQL.

• Knowledge of all common basic data structures and algorithms and how they are used is a must.

• Multilingual programming experience: our code base is primarily in Ruby, with a trend to migrate to GOlang and Rust. At least two languages are required.

• At least basic understanding of cloud deployments (k8s, Terraform, ArgoCD)

• Experience of working with public cloud infrastructure providers(AWS/Azure/Google Cloud).

• Excellent debugging, analytical, problem solving, and social skills.

• BS/MS degree in Computer Science, Engineering or a related subject, 7+ years of industry experience.

Optional

• Background in GOlang, Rust, WASM.

• Background in network programming.

• Background in Kotlin/Multiplatform. 

• Background in application, data security.

• Deep knowledge of physical DB design.

• Experience of working with Docker and other isolation technologies.

• Experience in related fields (DevOps, ML, DBA, Enterprise applications, etc).

• Experience in building/deploying data processing pipelines is a plus.

• Experience of working with third-party REST APIs at scale (request throttling, batch processing etc).

Soft Skills / Personal Characteristics

• Ability to technically lead projects. Work with requirements, cost analysis.

• Readiness to work remotely with teams distributed across the world and timezones.

(REQ ID: 2343)

Responsibilities

We are looking for an exceptional Senior Backend Developer (Ruby) to join our growing Engine team. The Engine team develops and maintains most things related to Workato Recipe runtime. Everything related to recipe execution: DSL, pulling events, processing webhooks, executing jobs. There are various aspects to it: performance, scaling, storage, durability, atomicity, concurrency guarantees, data protection, and encryption. 

 In this role, you will also be responsible to:

• Build/extend/troubleshot/fix complex heterogeneous GOlang and Ruby applications, as well as small self-contained GOlang microservices.

• Improve execution engine of custom third-party code (Ruby DSL, isolation, performance, new features).

• Write well designed, testable, efficient code in Ruby and GOlang.

• Integration of data storage solutions Postgres/S3/DynamoDB/Kafka/ClickHouse etc.

• Contribute in all phases of the development lifecycle.

• Provide code reviews to your teammates.

• Provide technical leadership. Work with other teams on shared projects.

• Evaluate and propose improvements to existing systems.

• Identify bottlenecks and bugs, and devise solutions to these problems.

• Help maintain code quality, organization and automatization.

• We always explore new technologies and work with Rust and Wasm can be foreseen.

Requirements

Qualifications / Experience / Technical Skills

• Strong experience in building scalable distributed backend applications (7+ years).

• Excellent understanding of distributed systems patterns and algorithms.

• Great understanding of all building blocks of large web applications: databases, load balancers, application servers, message brokers, caching, monitoring, etc.

• Excellent understanding of network protocols and stacks.

• Excellent understanding of DB technologies: classic databases and modern no-SQL.

• Knowledge of all common basic data structures and algorithms and how they are used is a must.

• Multilingual programming experience: our code base is primarily in Ruby, with a trend to migrate to GOlang and Rust. At least two languages are required.

• At least basic understanding of cloud deployments (k8s, Terraform, ArgoCD)

• Experience of working with public cloud infrastructure providers(AWS/Azure/Google Cloud).

• Excellent debugging, analytical, problem solving, and social skills.

• BS/MS degree in Computer Science, Engineering or a related subject, 7+ years of industry experience.

Optional

• Background in GOlang, Rust, WASM.

• Background in network programming.

• Background in Kotlin/Multiplatform. 

• Background in application, data security.

• Deep knowledge of physical DB design.

• Experience of working with Docker and other isolation technologies.

• Experience in related fields (DevOps, ML, DBA, Enterprise applications, etc).

• Experience in building/deploying data processing pipelines is a plus.

• Experience of working with third-party REST APIs at scale (request throttling, batch processing etc).

Soft Skills / Personal Characteristics

• Ability to technically lead projects. Work with requirements, cost analysis.

• Readiness to work remotely with teams distributed across the world and timezones.

(REQ ID: 2343)

Responsibilities

We are looking for an exceptional Senior Backend Developer (Ruby) to join our growing Engine team. The Engine team develops and maintains most things related to Workato Recipe runtime. Everything related to recipe execution: DSL, pulling events, processing webhooks, executing jobs. There are various aspects to it: performance, scaling, storage, durability, atomicity, concurrency guarantees, data protection, and encryption. 

 In this role, you will also be responsible to:

• Build/extend/troubleshot/fix complex heterogeneous GOlang and Ruby applications, as well as small self-contained GOlang microservices.

• Improve execution engine of custom third-party code (Ruby DSL, isolation, performance, new features).

• Write well designed, testable, efficient code in Ruby and GOlang.

• Integration of data storage solutions Postgres/S3/DynamoDB/Kafka/ClickHouse etc.

• Contribute in all phases of the development lifecycle.

• Provide code reviews to your teammates.

• Provide technical leadership. Work with other teams on shared projects.

• Evaluate and propose improvements to existing systems.

• Identify bottlenecks and bugs, and devise solutions to these problems.

• Help maintain code quality, organization and automatization.

• We always explore new technologies and work with Rust and Wasm can be foreseen.

Requirements

Qualifications / Experience / Technical Skills

• Strong experience in building scalable distributed backend applications (7+ years).

• Excellent understanding of distributed systems patterns and algorithms.

• Great understanding of all building blocks of large web applications: databases, load balancers, application servers, message brokers, caching, monitoring, etc.

• Excellent understanding of network protocols and stacks.

• Excellent understanding of DB technologies: classic databases and modern no-SQL.

• Knowledge of all common basic data structures and algorithms and how they are used is a must.

• Multilingual programming experience: our code base is primarily in Ruby, with a trend to migrate to GOlang and Rust. At least two languages are required.

• At least basic understanding of cloud deployments (k8s, Terraform, ArgoCD)

• Experience of working with public cloud infrastructure providers(AWS/Azure/Google Cloud).

• Excellent debugging, analytical, problem solving, and social skills.

• BS/MS degree in Computer Science, Engineering or a related subject, 7+ years of industry experience.

Optional

• Background in GOlang, Rust, WASM.

• Background in network programming.

• Background in Kotlin/Multiplatform. 

• Background in application, data security.

• Deep knowledge of physical DB design.

• Experience of working with Docker and other isolation technologies.

• Experience in related fields (DevOps, ML, DBA, Enterprise applications, etc).

• Experience in building/deploying data processing pipelines is a plus.

• Experience of working with third-party REST APIs at scale (request throttling, batch processing etc).

Soft Skills / Personal Characteristics

• Ability to technically lead projects. Work with requirements, cost analysis.

• Readiness to work remotely with teams distributed across the world and timezones.

(REQ ID: 2343)

Responsibilities

We are looking for an exceptional Senior Backend Developer (Ruby) to join our growing Engine team. The Engine team develops and maintains most things related to Workato Recipe runtime. Everything related to recipe execution: DSL, pulling events, processing webhooks, executing jobs. There are various aspects to it: performance, scaling, storage, durability, atomicity, concurrency guarantees, data protection, and encryption. 

 In this role, you will also be responsible to:

• Build/extend/troubleshot/fix complex heterogeneous GOlang and Ruby applications, as well as small self-contained GOlang microservices.

• Improve execution engine of custom third-party code (Ruby DSL, isolation, performance, new features).

• Write well designed, testable, efficient code in Ruby and GOlang.

• Integration of data storage solutions Postgres/S3/DynamoDB/Kafka/ClickHouse etc.

• Contribute in all phases of the development lifecycle.

• Provide code reviews to your teammates.

• Provide technical leadership. Work with other teams on shared projects.

• Evaluate and propose improvements to existing systems.

• Identify bottlenecks and bugs, and devise solutions to these problems.

• Help maintain code quality, organization and automatization.

• We always explore new technologies and work with Rust and Wasm can be foreseen.

Requirements

Qualifications / Experience / Technical Skills

• Strong experience in building scalable distributed backend applications (7+ years).

• Excellent understanding of distributed systems patterns and algorithms.

• Great understanding of all building blocks of large web applications: databases, load balancers, application servers, message brokers, caching, monitoring, etc.

• Excellent understanding of network protocols and stacks.

• Excellent understanding of DB technologies: classic databases and modern no-SQL.

• Knowledge of all common basic data structures and algorithms and how they are used is a must.

• Multilingual programming experience: our code base is primarily in Ruby, with a trend to migrate to GOlang and Rust. At least two languages are required.

• At least basic understanding of cloud deployments (k8s, Terraform, ArgoCD)

• Experience of working with public cloud infrastructure providers(AWS/Azure/Google Cloud).

• Excellent debugging, analytical, problem solving, and social skills.

• BS/MS degree in Computer Science, Engineering or a related subject, 7+ years of industry experience.

Optional

• Background in GOlang, Rust, WASM.

• Background in network programming.

• Background in Kotlin/Multiplatform. 

• Background in application, data security.

• Deep knowledge of physical DB design.

• Experience of working with Docker and other isolation technologies.

• Experience in related fields (DevOps, ML, DBA, Enterprise applications, etc).

• Experience in building/deploying data processing pipelines is a plus.

• Experience of working with third-party REST APIs at scale (request throttling, batch processing etc).

Soft Skills / Personal Characteristics

• Ability to technically lead projects. Work with requirements, cost analysis.

• Readiness to work remotely with teams distributed across the world and timezones.

(REQ ID: 2343)

Responsibilities

We are looking for an exceptional Senior Backend Developer (Ruby) to join our growing Engine team. The Engine team develops and maintains most things related to Workato Recipe runtime. Everything related to recipe execution: DSL, pulling events, processing webhooks, executing jobs. There are various aspects to it: performance, scaling, storage, durability, atomicity, concurrency guarantees, data protection, and encryption. 

 In this role, you will also be responsible to:

• Build/extend/troubleshot/fix complex heterogeneous GOlang and Ruby applications, as well as small self-contained GOlang microservices.

• Improve execution engine of custom third-party code (Ruby DSL, isolation, performance, new features).

• Write well designed, testable, efficient code in Ruby and GOlang.

• Integration of data storage solutions Postgres/S3/DynamoDB/Kafka/ClickHouse etc.

• Contribute in all phases of the development lifecycle.

• Provide code reviews to your teammates.

• Provide technical leadership. Work with other teams on shared projects.

• Evaluate and propose improvements to existing systems.

• Identify bottlenecks and bugs, and devise solutions to these problems.

• Help maintain code quality, organization and automatization.

• We always explore new technologies and work with Rust and Wasm can be foreseen.

Requirements

Qualifications / Experience / Technical Skills

• Strong experience in building scalable distributed backend applications (7+ years).

• Excellent understanding of distributed systems patterns and algorithms.

• Great understanding of all building blocks of large web applications: databases, load balancers, application servers, message brokers, caching, monitoring, etc.

• Excellent understanding of network protocols and stacks.

• Excellent understanding of DB technologies: classic databases and modern no-SQL.

• Knowledge of all common basic data structures and algorithms and how they are used is a must.

• Multilingual programming experience: our code base is primarily in Ruby, with a trend to migrate to GOlang and Rust. At least two languages are required.

• At least basic understanding of cloud deployments (k8s, Terraform, ArgoCD)

• Experience of working with public cloud infrastructure providers(AWS/Azure/Google Cloud).

• Excellent debugging, analytical, problem solving, and social skills.

• BS/MS degree in Computer Science, Engineering or a related subject, 7+ years of industry experience.

Optional

• Background in GOlang, Rust, WASM.

• Background in network programming.

• Background in Kotlin/Multiplatform. 

• Background in application, data security.

• Deep knowledge of physical DB design.

• Experience of working with Docker and other isolation technologies.

• Experience in related fields (DevOps, ML, DBA, Enterprise applications, etc).

• Experience in building/deploying data processing pipelines is a plus.

• Experience of working with third-party REST APIs at scale (request throttling, batch processing etc).

Soft Skills / Personal Characteristics

• Ability to technically lead projects. Work with requirements, cost analysis.

• Readiness to work remotely with teams distributed across the world and timezones.

(REQ ID: 2343)

Responsibilities

We are looking for a Senior Rust Software Developer. In this role, you will also be responsible to:

• Building new products inside the company.

• Develop new code with Rust, and deal with existing Go/Ruby code

• Create PoC in the new areas and drive them to production or drop them away.

Requirements

Qualifications / Experience / Technical Skills

• Strong experience writing, shipping, and maintaining Rust code (2+ years), and experience with other languages (Ruby, Python, Go, JS, Java, etc.)
  
  
• Knowledge of basic data structures and algorithms, multiprocessing, memory management.
  
  
• Experience developing high-performance asynchronous applications with Rust (preferably tokio).
  
  
• Good understanding of network protocols and stacks.
  
  
• Good understanding of DB technologies: classic databases and modern no-SQL.
  
  
• Basic knowledge of DevOps practices and tools
  
  
• Understanding of Linux environment
  
  
• Golang/Ruby knowledge is a plus
  
  
• Experience working with WASM is a plus
  
  
• Open Source contributions is a plus

Soft Skills / Personal Characteristics

• Readiness to work remotely with teams distributed across the world and timezones
  
  
• Spoken English (at the level enough to pass the technical interview and later work with colleagues)
  
  
• Being a result-oriented problem solver.
  
  
• Prefers coming up with proposals in problematic areas, rather than being passive.
  
  
• Being open to new technologies and switching between projects.
  
  
• Readiness to travel for business

(REQ ID: 2682)

Responsibilities

We are looking for a Senior Rust Software Developer. In this role, you will also be responsible to:

• Building new products inside the company.

• Develop new code with Rust, and deal with existing Go/Ruby code

• Create PoC in the new areas and drive them to production or drop them away.

Requirements

Qualifications / Experience / Technical Skills

• Strong experience writing, shipping, and maintaining Rust code (2+ years), and experience with other languages (Ruby, Python, Go, JS, Java, etc.)
  
  
• Knowledge of basic data structures and algorithms, multiprocessing, memory management.
  
  
• Experience developing high-performance asynchronous applications with Rust (preferably tokio).
  
  
• Good understanding of network protocols and stacks.
  
  
• Good understanding of DB technologies: classic databases and modern no-SQL.
  
  
• Basic knowledge of DevOps practices and tools
  
  
• Understanding of Linux environment
  
  
• Golang/Ruby knowledge is a plus
  
  
• Experience working with WASM is a plus
  
  
• Open Source contributions is a plus

Soft Skills / Personal Characteristics

• Readiness to work remotely with teams distributed across the world and timezones
  
  
• Spoken English (at the level enough to pass the technical interview and later work with colleagues)
  
  
• Being a result-oriented problem solver.
  
  
• Prefers coming up with proposals in problematic areas, rather than being passive.
  
  
• Being open to new technologies and switching between projects.
  
  
• Readiness to travel for business

(REQ ID: 2682)

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 and independent with no VC control. 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 role:

As an engineer on our small Windows VPN team, you will be responsible for designing, building, maintaining, and evolving Proton’s applications on Windows. You will be involved in the entire application lifecycle, from feature design and implementation to CI/CD configuration, deployment, monitoring, and operational incident response. You will collaborate closely with product managers and engineers across the company to deliver privacy‑preserving products used by millions of people worldwide.

Our codebase is primarily written in .NET and WinUI (C#/XAML), and we are building and integrating cross‑platform logical core libraries written in Rust.

Software quality is central to this role. You will help define, maintain, and improve our testing stack, which includes unit tests, integration tests, and automated GUI tests (using FlaUI).

What we are looking for:

• Strong experience in C# and .NET development.

• Strong experience building and maintaining Windows desktop applications using frameworks such as WinUI, WPF, or similar.

• Solid understanding of MVVM architecture, dependency injection, asynchronous programming (async/await), and event‑based messaging patterns.

• Proven ability to write maintainable, well‑tested, and scalable codebases.

• Demonstrated experience driving change within an organization and leading complex technical projects

• A strong understanding of software architecture and engineering best practices.

• An appreciation for user experience and design quality.

• Rust experience is not required but is a significant plus.

• Working knowledge of networking fundamentals (TCP/IP, DNS, routing concepts) and an interest in VPN technologies and protocols.

• Experience with code debugging, profiling, and performance optimization on Windows.

• Familiarity with Git-based workflows, CI/CD pipelines (GitLab) and modern collaborative development practices.

• Experience with gradual rollout, and observability tooling (telemetry, metrics, monitoring and alerting).

Even if you don’t meet every requirement listed above, if you’re passionate about privacy and believe you could be a great fit, we encourage you to 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.

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.

#LI-ONSITE

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 Payments Team

The goal of the Payments team is to enable revenue generation for the entire Proton ecosystem. This comes in the form of introducing new payment methods for users to architecting our client libraries. This team has impact across all of Proton's products and is critical to the success of the business as a whole.

• As Proton is a global Company, the Payments Team works to continuously expand the possibilities for users to pay with various payment methods, beyond just plain credit cards or Paypal.
• The team works in tight collaboration with the Account Team (responsible for the Proton user lifecycle), the Proton Finance team, and every single Business Unit to ensure that plans, promotions and pricing meet user expectations.
• The mission of the team is to empower anyone in the world who wish to use Proton services, to become a Proton subscriber by building enticing interfaces, being able to progressively reach global markets, by providing the methods and tooling allowing users to pay, and for the Proton organization to properly being able to measure growth, and to follow the relative financial regulations

Tech Stack and Tools:

• Differently than many other stacks at Proton, the Payments stack depends largely on external services such as payment providers, tax-information providers, currency-conversion providers... As such it is critical, for the success of the service, to build with resilience.
• Internally our backend code is in general based on PHP/Symfony, our frontend is based on React, our mobile code is based on Kotlin (on Android) and on Swift (on iOS), with a growing shared codebase in Rust.
• All our client-code is open-source and GPL3.
• We are migrating our infrastructure to Kubernetes.
• Everything runs on premise in Proton's data-centers.
• To organize our work we use classic tools such as Jira and Confluence.

Future Plans:

• With payments being the backbone of any subscription business, we have ambitious plans to expand the team to cover a wide breadth of topics ranging from demystifying payment performance data across regions/products, to thinking about the holistic strategy of product catalogs, and everything in between. This particular team requires someone who is a strong generalist, who thrives with ambiguity. There's huge potential for growth no matter the domain, and the outcome for any candidate is an in-depth view into how money moves globally.

What you will do:

• Build features in all of Proton's products.
• Close interactions with products and engineers across the company.
• Build scalable software architecture through software engineering best practices.
• Optimise user experience and design.

Job requirements:

• Proven experience with back-end development 
• Expertise in building scalable, high-performance solutions
• Proficiency with profiling techniques and performance optimization tools
• Experience leading a team initiative from discovery to production
• Strong understanding of SQL (MySQL preferred) and data modeling best practices
• Familiarity with Redis or other caching technologies for performance optimization
• Knowledge of security best practices and experience implementing secure software solutions
• In-depth understanding of HTTP/REST, including both the development and consumption of web-based APIs
• Solid grasp of cryptographic concepts, including key exchange, and the distinction between symmetric and asymmetric encryption

Bonus points for: 

• Experience within the payments domain

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

• 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)
• Work with smart and dedicated people - 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.

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.

#LI-ONSITE

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 to 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!

Purpose of the role:  

Proton continues to grow rapidly as increasing numbers of people across the globe seek greater privacy controls of their information online. To accelerate our growth, we are seeking a senior leader to drive engineering for one of our many existing or upcoming Products.

We are seeking a Director of Engineering to one of our existing or upcoming Products. This role involves setting and executing technical strategy, team management, and working closely with your senior product managers counterparts, to ensure high-velocity delivery of new products.

As a key member of the engineering leadership team, you will shape the company’s technical strategy and contribute to Proton’s mission of creating a privacy-centric internet. Each product will have its unique challenges and areas of focus, nevertheless we require all Engineering Directors for our Products to have a demonstrated track record of building and scaling customer facing applications, in either a B2C or B2B context, for millions of users, across multiple platforms (mobile, desktop, backend systems and platforms).

In addition to technical expertise, Engineering Directors as senior leaders within Proton, have excellent communication skills, a business mindset, and a strong sense of empathy for the end customers.

What you will do:

• Setting technical direction and vision for one of our Products
• Lead technical design and platform discussions
• Drive continuous improvement in our DevSecOps practices, and improve lead times and time to market while maintaining exceptional standards of product quality
• Hold yourself and team accountable for timely delivery of scalable, quality-focus user experiences and features
• Develop efficient processes, and motivate your team to operate with high velocity, ownership, and accountability
• Lead through others, and develop the next generation of engineering leaders at Proton
• Inspire, coach, and develop your teams
• Optimize your organizational structure, and continuously raise the bar on hiring
• Build strong relationships with senior leaders, and advance your long-term platform and engineering vision
• Contribute to Proton's technology and open source communities
• Foster an inclusive and diverse environment for your team to show up and give their best each day

Our Tech stack:

• Applied cryptography (PGP, TLS, etc.)
• REST APIs
• Event architectures 
• HTTP networking
• SQL, Redis
• PHP (Symfony), Rust, Python
• iOS, macOS (Swift)
• Android (Kotlin, Jetpack)
• Web (Typescript, React)
• Desktop (C#, Swift)
• Infrastructure: MySQL / Ceph

We need you to have:

• Experience in software engineering in progressively complex roles
• Experience directly leading and managing engineers
• Demonstrable experience as a manager of managers
• A history of collaboration with senior leaders in engineering, product on developing technical and product strategy
• Great empathy and collaboration skills, and even greater resilience
• A curious, passionate, and growth-oriented mindset
• Deep experience as a hands-on software engineer creating well-crafted, maintainable systems
• Mobile-first background (ideally former mobile developer)
• Practical experience leading DevOps and SRE initiatives and driving best practices
• Experience with cryptography preferred
• Bonus points for each of the following:

• • Experience with performance tuning and scaling across client, backend, infrastructure
  • Working closely with C-level executives to align on direction, vision and execution
  • Having both, the experience of operating at global scale with millions of customers but also thriving in the chaotic growth phase of scaling up to reach it.

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.

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.

#LI-ONSITE

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!

The Payments Team

The goal of the Payments team is to enable revenue generation for the entire Proton ecosystem. This comes in the form of introducing new payment methods for users to architecting our client libraries. This team has impact across all of Proton's products and is critical to the success of the business as a whole.

• The Payments Team works to continuously expand the possibilities for users to pay with various payment methods, beyond just plain credit cards or Paypal - we aspire to create the best end to end payments experience for users globally
• The team works in tight collaboration with the Account Team (responsible for the Proton user lifecycle), the Proton Finance team, and every single Business Unit to ensure that plans, promotions and pricing meet user expectations -- we are the most cross-functional team in the business with direct impact on the ecosystem strategy

Tech Stack and Tools:

• Differently than many other stacks at Proton, the Payments stack depends largely on external services such as payment providers, tax-information providers, currency-conversion providers... As such it is critical, for the success of the service, to build with resilience.
• Internally our backend code is in general based on PHP/Symfony, our frontend is based on React, our mobile code is based on Kotlin (on Android) and on Swift (on iOS), with a growing shared codebase in Rust.
• All our client-code is open-source and GPL3.
• We are migrating our infrastructure to Kubernetes.
• Everything runs on premise in Proton's data-centers.
• To organize our work we use classic tools such as Jira and Confluence.

Future Plans:

• With payments being the backbone of any subscription business, we have ambitious plans to expand the team to cover a wide breadth of topics ranging from demystifying payment performance data across regions/products, to thinking about the holistic strategy of product catalogs, and everything in between. This particular team requires someone who is a strong generalist, who thrives with ambiguity. There's huge potential for growth no matter the domain, and the outcome for any candidate is an in-depth view into how money moves globally.

What you will do:

• Build features in all of Proton's products.
• Close interactions with products and engineers across the company.
• Build scalable software architecture through software engineering best practices.
• Optimise user experience and design.

As a Front-end Engineer at Proton, you will play a crucial role in developing Proton's most vital services and serving over 100 million users worldwide. We expect you to be customer-centric, continuously learning, passionate about technology and usability. You are 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.

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.
• 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 integration tests, to ensure the reliability of core libraries.
• Management: Break down large initiatives into smaller milestones to gather stakeholder feedback quickly, allowing us to course-correct immediately. 

Job Requirements:

• Deep understanding of JavaScript methodologies and design patterns
• Proficiency with TypeScript or any typed language
• Experience with React or 2+ similar frameworks, developing performant and reusable components
• Strong understanding of software engineering best practices, such as SOLID, 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: 

• 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
• Experience with Grafana or other monitoring platforms
• Experience with breaking down product requirements into architecture design and implementation
• Experience with NodeJS
• High-level understanding of cryptography concepts such as key exchange and the difference between symmetric and asymmetric encryption 

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.

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.

#LI-ONSITE

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:

ProtonVPN runs on a distributed architecture of Linux servers and a set of apps available on each major platform (Windows, Android, iOS, macOS, and Linux) that interact with our infrastructure.

As a member of the ProtonVPN Research and Development team, you will work on maintaining the security of ProtonVPN’s infrastructure, improving its overall performance, designing and implementing new features. On any given day, you might code in C or Rust, script in Python or Lua, create patches for the Linux kernel, or debug system-level issues on different operating systems. You will work in close collaboration with the entire ProtonVPN development team on any outstanding projects. You will face unique and varied challenges that will require continuous  learning.

What you will do:

• Being an active member of the ProtonVPN R&D team

• Collaborating with app developers to help solve the various complex challenges related to (but not limited to) the networking stack of Linux, macOS, iOS, Android, and Windows systems

• Helping develop innovative solutions to improve the connectivity, stability, performance, scalability, security, and resilience of ProtonVPN’s infrastructure and client software, and extend their functionality

• Contributing to existing open-source projects or creating new ones

What we are looking for:

• Expert-level knowledge of operating system internals

• Expertise with network protocols and implementation

• A documented track record of contributions to system-level projects and applications

• Experience with software development

• Understanding of the principles of quality assurance

Bonus points for: 

• Expertise in Windows, macOS, or Linux system development

• Extensive experience working with Linux kernel, Windows drivers, or macOS system extensions development

• Strong understanding of system programming languages (C/C++, Rust, Go, Python, etc.)

• Experience with debugging code and code profiling

• Good understanding of TCP/IP protocol and settings (e.g., congestion algorithms)

• Strong understanding of VPN protocols (particularly OpenVPN and WireGuard)

• Experience with cryptography concepts (e.g., TLS certificates and public key infrastructure)

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.

#LI-Onsite

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 organisations 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, coming 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. We believe smaller teams of exceptional talent will always prevail over larger teams with lower talent density. You'll have the opportunity to 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!

Role overview

As a fullstack cross-platform Senior Android Engineer, you'll play a pivotal role in developing Proton Pass using Jetpack Compose and Rust. You’ll lead with an end-to-end ownership approach, ensuring timely delivery of high-quality, scalable solutions that will delight our customers. Your ambition and enthusiasm will drive innovation and excellence both in Proton Pass and SimpleLogin products.

Key responsibilities

• Develop and maintain cross-platform mobile applications for Android using a blend of cross-platform (Rust) and native technologies (Kotlin)
• 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 mobile development – we tackle complex engineering challenges with creativity and ingenuity
• Optimise mobile applications for performance, usability and responsiveness across different devices and screen sizes
• Master memory management, multithreading and concurrency mechanisms to enhance performance and responsiveness of mobile applications
• Design for scalability, considering factors such as data caching, network bandwidth and server load
• Prioritise customer satisfaction by maintaining a customer-centric mindset throughout the development process, continuously seeking feedback and iterating to improve the user experience

The ideal candidate will bring

• Bachelor's degree in Computer Science, Engineering or related field (or equivalent work experience)
• Excellent problem-solving skills and the ability to think outside the box to overcome challenges
• Passion for continuous learning and driving change in the rapidly evolving field of mobile development
• Excellent communication and interpersonal skills
• Proven experience developing mobile applications for Android using Kotlin
• Proficiency with Jetpack Compose for Android, and familiarity with Rust
• Strong understanding of mobile app architecture, design patterns and best practices
• Knowledge of memory management techniques and best practices
• Experience with multithreading and concurrency in mobile applications
• Good understanding of scalability considerations when it comes to engineering mobile applications
• Previous experience working in a fast-paced, scale-up environment

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

What we offer

• 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
• Learning & Development: we are committed to your professional growth – Proton offers various learning opportunities, including training programs, conferences/events and continual learning
• Employee Benefits: comprehensive health insurance plans, competitive retirement savings options, generous vacation/leave policies and wellness programs
• Stock Options: at Proton, we are all owners of the company and you get stock options when you join us
• In-Person Collaboration: 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 enjoy working from home for up to 30% of the time, while enjoying great company culture during our three core days in the office (depending on the role, fully remote positions may also be available)
• Food: lunch and snacks are provided by Proton every day at our offices
• Transport: we'll always support our employees with transport costs through subsidising public transport, bike allowances or parking spaces based on your office location
• Flexible Working: you can define your own working hours as long as it works with team meetings
• Work that Matters: Proton is a community-first organisation, 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)

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 its 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 anonymise 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 CVs 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.

#LI-ONSITE

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 Payments Team

The goal of the Payments team is to enable revenue generation for the entire Proton ecosystem. This comes in the form of introducing new payment methods for users to architecting our client libraries. This team has impact across all of Proton's products and is critical to the success of the business as a whole.

• As Proton is a global Company, the Payments Team works to continuously expand the possibilities for users to pay with various payment methods, beyond just plain credit cards or Paypal.
• The team works in tight collaboration with the Account Team (responsible for the Proton user lifecycle), the Proton Finance team, and every single Business Unit to ensure that plans, promotions and pricing meet user expectations.
• The mission of the team is to empower anyone in the world who wish to use Proton services, to become a Proton subscriber by building enticing interfaces, being able to progressively reach global markets, by providing the methods and tooling allowing users to pay, and for the Proton organization to properly being able to measure growth, and to follow the relative financial regulations

Tech Stack and Tools:

• Differently than many other stacks at Proton, the Payments stack depends largely on external services such as payment providers, tax-information providers, currency-conversion providers... As such it is critical, for the success of the service, to build with resilience.
• Internally our backend code is in general based on PHP/Symfony, our frontend is based on React, our mobile code is based on Kotlin (on Android) and on Swift (on iOS), with a growing shared codebase in Rust.
• All our client-code is open-source and GPL3.
• We are migrating our infrastructure to Kubernetes.
• Everything runs on premise in Proton's data-centers.
• To organize our work we use classic tools such as Jira and Confluence.

Future Plans:

• With payments being the backbone of any subscription business, we have ambitious plans to expand the team to cover a wide breadth of topics ranging from demystifying payment performance data across regions/products, to thinking about the holistic strategy of product catalogs, and everything in between. This particular team requires someone who is a strong generalist, who thrives with ambiguity. There's huge potential for growth no matter the domain, and the outcome for any candidate is an in-depth view into how money moves globally.

What you will do:

• Build features in all of Proton's products.
• Close interactions with products and engineers across the company.
• Build scalable software architecture through software engineering best practices.
• Optimise user experience and design.

Job requirements:

• Proven experience with back-end development 
• Expertise in building scalable, high-performance solutions
• Proficiency with profiling techniques and performance optimization tools
• Experience leading a team initiative from discovery to production
• Strong understanding of SQL (MySQL preferred) and data modeling best practices
• Familiarity with Redis or other caching technologies for performance optimization
• Knowledge of security best practices and experience implementing secure software solutions
• In-depth understanding of HTTP/REST, including both the development and consumption of web-based APIs
• Solid grasp of cryptographic concepts, including key exchange, and the distinction between symmetric and asymmetric encryption

Bonus points for: 

• Experience within the payments domain

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

• 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)
• Work with smart and dedicated people - 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.

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.

#LI-ONSITE

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 Pass Team

Proton Pass is a secure, open-source password manager developed by Proton—the team behind Proton Mail and Proton VPN. Built with end-to-end encryption and a strong commitment to privacy, Proton Pass helps individuals and teams safely manage passwords, 2FA codes, notes, and more. As part of the Proton ecosystem, it integrates seamlessly with other privacy-first tools, ensuring robust protection for your digital identity.

What you will do:

We're seeking an experienced developer working across multiple web platforms including browser extensions, web and desktop applications. This role requires both front-end expertise and deep technical knowledge of browser internals, extension APIs, and desktop application frameworks

• 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. (read more about our impact here)
• 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.

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.

#LI-ONSITE

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 to 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!

The Drive Team:

Proton Drive is our end-to-end encrypted cloud storage service that makes privacy simple and accessible. Built on the same security principles that power Proton Mail, Proton Drive ensures that files, photos, and documents remain fully encrypted—both in transit and at rest—so only you can access them. Available on web, desktop, and mobile, it enables users to securely store, share, and collaborate without sacrificing privacy or control. By offering a truly private alternative to Big Tech’s data-driven ecosystems, Proton Drive plays a key role in building an internet where privacy is the default.

The Role:

Proton is a mobile-first company building an Internet that respects privacy and puts people, not advertisers, first. As an engineer on our Apple team you’ll build and ship features across Proton’s apps on iPhone, iPad and macOS, working closely with product and engineers across the company to define what “great” looks like on Apple platforms. Our codebase is primarily Swift with some Go, and we’re moving to a platform-independent Rust logical core that communicates with Swift via a generic interface, so Rust experience is a strong plus. Quality is central to the role: you’ll contribute to and maintain our testing stack, including unit tests for business logic, stubbed API tests for pseudo-integration, snapshot tests for UI and XCUITest for end-to-end user flows. You’ll join a team that pairs deep technical expertise with an obsession for simple, usable interfaces, shipping privacy-preserving products used by millions.

We we are looking for:

• You have experience in iOS or macOS development, in particular with Swift (7+ years)
• You have a passion for mentoring other engineers and helping them grow
• You are passionate about user interaction, usability, and providing an excellent user experience
• Demonstrated experience driving change within an organization and leading complex technical projects
• Extensive experience building maintainable and testable code bases, including API design and unit testing techniques
• Extensive experience with multithreading programming and mobile memory management
• A strong grasp of scalable software architecture and software engineering best practices
• An intuition for optimal user experience and design

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.

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.

#LI-ONSITE

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 organisations 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, coming 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'll have the opportunity to 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!

The Payments Team

The goal of the Payments team is to enable revenue generation for the entire Proton ecosystem. This comes in the form of introducing new payment methods for users to architecting our client libraries. This team has impact across all of Proton's products and is critical to the success of the business as a whole.

• The Payments Team works to continuously expand the possibilities for users to pay with various payment methods, beyond just plain credit cards or Paypal - we aspire to create the best end to end payments experience for users globally
• The team works in tight collaboration with the Account Team (responsible for the Proton user lifecycle), the Proton Finance team, and every single Business Unit to ensure that plans, promotions and pricing meet user expectations -- we are the most cross-functional team in the business with direct impact on the ecosystem strategy

The Role

As an engineer on our iOS team you’ll build and ship features across Proton’s apps on iPhone, working closely with product and engineers across the company to define what “great” looks like on Apple platforms. Our codebase is primarily Swift with some Go, and we’re moving to a platform-independent Rust logical core that communicates with Swift via a generic interface, so Rust experience is a strong plus but not essential. Quality is central to the role: you’ll contribute to and maintain our testing stack, including unit tests for business logic, stubbed API tests for pseudo-integration, snapshot tests for UI and XCUITest for end-to-end user flows. You’ll join a team that pairs deep technical expertise with an obsession for simple, usable interfaces, shipping privacy-preserving products used by millions.

What we are looking for:

• You have experience in iOS in particular with Swift
• You have a passion for mentoring other engineers and helping them grow
• You are passionate about user interaction, usability, and providing an excellent user experience
• Demonstrated experience driving change within an organisation and leading complex technical projects
• Extensive experience building maintainable and testable code bases, including API design and unit testing techniques
• Extensive experience with concurrent programming and mobile memory management
• A strong grasp of scalable software architecture and software engineering best practices
• An intuition for optimal user experience and design
• Rust experience not required, but a major plus
• Deep understanding of APNs, UNUserNotificationCenter and iOS background execution (silent pushes, background app refresh, background URLSession), and how these impact app reliability
• Experience building offline-first data flows with local persistence (Core Data, SQLite, Realm or similar) and conflict-free sync

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.

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.

#LI-ONSITE

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 to 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!

The team:

• The goal of the Payments team is to enable revenue generation for the entire Proton ecosystem. This comes in the form of introducing new payment methods for users to architecting our client libraries. This team has impact across all of Proton's products and is critical to the success of the business as a whole.
• Drive Foundation is the backbone of Proton Drive. We develop the Proton Drive SDKs, the core of all of Proton Drive's client applications as well as the cornerstone of Drive into other Proton applications, businesses, and 3rd parties. We ensure that cross-client and backend initiatives are executed with consistency and correctness; we also build and maintain the core documentation for Drive and define the architectural roadmap to evolve Drive's technology, both server-side and client-side.

• We use standard tools for communication and work organization (Git, GitLab, GitHub, GitLab CI, Jira, Confluence). Languages we see daily is C# and TypeScript. We also need to provide bindings for Swift and Kotlin, and we plan to add Rust to avoid the need to have two SDK implementations. We use Grafana and Prometheus to instrument our SDK, Sentry to get details issues from the SDK usage, GitLab CI for running tests including e2e tests written using Playwright for both SDKs, or GitLab in general to work on the code base.

Purpose of the role: 

As a Senior Rust Developer on our team, you will play a crucial role in designing, implementing, and maintaining components that power Proton Drive and Payments. You will work collaboratively in a cross-functional team, including backend API, web frontend, Mac, Windows, and Android/iOS mobile developers, to ensure seamless integration and optimal performance across various client applications.

What you will do:

• Architect and develop core libraries: Lead the design and development of core Rust libraries that serve as the backbone for Proton web and mobile applications.
• Cross-platform compatibility: Ensure compatibility and optimal performance across various platforms, including web browsers and mobile devices.
• Code review and optimization: Conduct code reviews and provide constructive feedback to ensure code quality, maintainability, and performance optimization.
• Collaboration: Work closely with frontend and mobile developers.
• Security: Implement and adhere to best practices in secure coding to maintain the high level of security and privacy Proton is known for.
• Testing: Develop and implement comprehensive testing strategies, including unit tests and integration tests, to ensure the reliability of core libraries.
• Documentation: Create and maintain thorough documentation for core libraries to assist other developers in understanding and utilizing the components.
• Continuous learning: Stay updated on the latest advancements in Rust and related technologies to suggest improvements and innovations.

Job requirements:

• Experience: 5+ years of professional software development experience, with a focus on Rust programming language.
• Rust proficiency: Strong expertise in Rust language features, concurrency, and ownership model.
• Web and/or mobile development: Experience in developing libraries for both web and mobile applications.
• Collaborative skills: Proven ability to work collaboratively in a team environment and excellent communication skills.
• Problem-solving: Strong problem-solving skills and the ability to troubleshoot issues efficiently.
• Security focus: Understanding of secure coding practices and a commitment to maintaining high levels of security and privacy.
• Version control: Proficient in using version control systems, preferably Git.
• Bachelor's or Master's degree: In Computer Science, Software Engineering, or a related field.

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. 
• 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.

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.

#LI-Onsite

We are looking for a Senior MLOps Engineer to add to our Data team in Barcelona.

Join the User Acquisition MLOps team that builds the core ML backbone of Appodeal. We design and run the systems that power real-time predictions at massive scale, where every millisecond matters. Our work directly drives thousands of bidding operations each second, supporting a high‑throughput, low‑latency inference platform used across the company.

You will help shape and evolve a modern ML platform built around Databricks, MLflow, Unity Catalog, GitHub Actions, and deep integrations with our Predictor service. This means solving real engineering challenges: scaling training pipelines, optimizing GPU workloads, ensuring safe and automated model promotions, and keeping online inference reliable under extreme load.

You will collaborate daily with Data Science, Data Engineering, Runtime, DevOps, and Product, and you will fully own the systems and projects you touch. This is a role for engineers who like autonomy, impact, and building things that matter.

Responsibilities:

• Design, operate, and improve the ML platform, including Databricks workflows for training, MLflow and Unity Catalog for model management, CI/CD pipelines using GitHub Actions and Databricks Asset Bundles, and integration with the runtime inference layer.
• Support data scientists in developing and maintaining end-to-end training pipelines, covering data processing, feature transformations, ML model training on GPUs, and distributed training setups to ensure efficient and scalable workflows.
• Ensure reliable and safe model inference by validating models before promotion, checking metadata compatibility, monitoring latency, and supporting model evaluation flows.
• Maintain strong ML observability, including online and offline monitoring, data and feature parity checks, and automated validation of model performance in production.
• Develop internal tools and APIs that enable DS teams and account managers to experiment, validate, and promote models efficiently while reducing operational friction.

Requirements:

• 3+ years of experience in MLOps, ML Platform Engineering, or Backend roles supporting production ML systems.
• Strong Python and software engineering skills, with experience building and maintaining APIs (FastAPI, Flask, or similar).
• Hands-on experience with DNNs using PyTorch or other modern deep learning frameworks, including GPU training and optimizing hardware utilization.
• Solid understanding of distributed computing and data processing using Apache Spark or similar frameworks.
• Experience with Databricks (Jobs, MLflow, Delta, UC) or an equivalent cloud-based ML platform.
• Strong understanding of the ML lifecycle: data ingestion, experimentation, model packaging, deployment, and monitoring.
• Familiarity with real-time model inference systems and ensuring compatibility with downstream services.
• Experience with data validation libraries (Pydantic or similar) used within ML and API workflows.
• Good understanding of Docker containers, Kubernetes, and basic networking concepts.
• Experience creating and maintaining CI/CD pipelines (GitHub Actions or similar).
• Experience with orchestration tools (Databricks Jobs, Dagster, Airflow or similar).
• Demonstrated ability to use modern AI tools (Claude, ChatGPT, Gemini) to improve development speed and quality.
• Proactive mindset with a strong sense of ownership, consistently pushing work forward and anticipating next steps without needing close direction.
• Strong English communication skills.

Nice to have:

• Exposure to very high-load, low-latency ML inference environments.
• Knowledge of distributed or large-scale ML training frameworks and multi-GPU setups.
• Familiarity with Databricks Asset Bundles.
• Understanding of ONNX or other portable model serialization formats.
• Ability to work with Rust programming language.
• Familiarity with transformer architectures, encoder-decoder models, or sequence modeling approaches.
• Exposure to data engineering concepts, such as building scalable data pipelines, understanding CDC patterns, or working with structured and unstructured datasets.
• Experience with MinIO or other S3-compatible storage systems.
• Understanding of networking protocols such as TCP, HTTP, and gRPC, including their limitations in low-latency scenarios.
• Confidence navigating the Atlassian ecosystem (Jira, Confluence, Compass).

This position supposes relocation to Barcelona and work from our office in the city center.

Why Join Us:

• Opportunity to work on cutting-edge projects with a global impact in the mobile app industry.
• A collaborative and inclusive work culture that values innovation and continuous learning.
• Competitive salary, flexible work arrangements, and a comprehensive benefits package.
• Professional development opportunities and career growth prospects within a fast-growing company.

About Appodeal

Appodeal is a dynamic US-based product company with a truly global presence.

We have offices in Warsaw, Barcelona, and Parkland (FL), along with remote team members located around the world.

Our company thrives on diversity, collaboration, and innovation, making us a leader in the mobile app monetization space.

Why Appodeal?

At Appodeal, we’re more than just a company—we’re a team united by a common mission:
Help people discover and grow their talents through products that enable successful mobile app businesses.

We take pride in our cutting-edge product and our internationally distributed team of talented professionals.

Here’s what we value:

• Continuous Learning and Growth – We invest in development and long-term careers
• Making an Impact – We are building a history-defining company in the mobile industry
• Solving Exciting Challenges – Complex, large-scale problems are part of our daily work
• Enjoying the Journey – We believe great results come with a positive environment

About the Role

We are looking for a Senior Rust Engineer to join our Barcelona team and contribute to building high-performance, real-time systems powering our ML-driven AdTech platform (Mobile Growth Platform).

In this role, you will work on core backend infrastructure and ML platform components, focusing on low-latency, high-load services that process large-scale traffic in real time.

You will play a key role in developing and optimizing systems such as real-time applications, feature stores, user identity services, and custom inference layers, ensuring scalability, reliability, and performance.

Responsibilities

• Contribute to the development of real-time applications and ML platform components
• Build and maintain high-load, low-latency backend services
• Work on in-house solutions including:
  • Feature stores
  • User identity services
  • Custom inference layer
  • ML platform infrastructure
• Optimize system performance across on-premise Docker & Kubernetes environments
• Design and implement solutions for traffic scaling and system reliability
• Collaborate with ML, data, and engineering teams to support production ML systems
• Continuously improve system architecture, observability, and efficiency

Tech Stack

• Languages: Rust, Python
• Data & Streaming: Kafka, SQL, Redis, ScyllaDB, Delta Lake, Databricks
• Infrastructure: Docker, Kubernetes (on-premise)
• Tools: GitHub

Requirements

• 5+ years of experience in software engineering
• Strong proficiency in Rust
  or
  proficiency in C/C++/Zig with willingness to transition to Rust
• Experience designing and building high-load, performance-critical systems
• Solid understanding of system design, concurrency, and performance optimization
• Basic knowledge of machine learning workflows and tools

Nice to Have

• System programming experience (C, C++, Zig)
• Experience in ML engineering / MLOps
• Strong Python skills
• Familiarity with AdTech standards (OpenRTB, MRAID, VAST)
• Experience with WASM / WASI
• Background in distributed systems and real-time processing
• Location: Barcelona, Spain (office attendance 4 days per week)

What We’re Looking For

• Autonomous and self-driven engineer with strong ownership mindset
• Passion for engineering excellence, performance, and scalability
• Interest in ML/AI systems and infrastructure
• Ability to work independently and make informed decisions
• Strong collaboration and communication skills

Why Join Us:

• Opportunity to work on cutting-edge projects with a global impact in the mobile app industry.
• A collaborative and inclusive work culture that values innovation and continuous learning.
• Competitive salary, flexible work arrangements, and a comprehensive benefits package.
• Professional development opportunities and career growth prospects within a fast-growing company.

We appreciate teamwork, critical thinking, independent decision-making, and standing up for oneʼs viewpoint.
We are looking for talented engineers who are willing to grow, improve and share our values!