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- Tasks: Lead the development of our secure email app, C.Email, using React Native.
- Company: Join Certonymity, a cutting-edge start-up revolutionising secure communication technology.
- Benefits: Enjoy competitive salary, flexible remote work, and opportunities for professional growth.
- Why this job: Make a real impact on how millions communicate securely with innovative tech.
- Qualifications: Extensive experience in React Native and automated testing required.
- Other info: Dynamic team environment with excellent career advancement opportunities.
The predicted salary is between 36000 - 60000 ÂŁ per year.
Certonymity is developing the next generation of secure communication technology. Our mission is to make encrypted email simple and widely accessible by combining advanced cryptography with real‑world identity verification. Our first product, C.Email, enables users to send and receive fully end‑to‑end encrypted messages without depending on third parties or complicated configurations. Each user has a verified digital identity, connected to their passport yet kept completely private through cryptographic keys — maintaining anonymity while ensuring accountability.
We are an ambitious, self‑funded start‑up with founders who have backgrounds in AI, Hedge Funds, Biotech, and Energy Production. Headquartered in London, our technical team is distributed across the UK and France. Working independently allows us to move quickly, innovate freely, and stay focused on creating cutting‑edge cryptographic, blockchain, and mobile‑first privacy tools.
About the Role
We’re seeking a Senior React Native Engineer to help build, refine, and scale our encrypted email application, C.Email. You’ll collaborate closely with our CTO, cryptography expert, and engineering team to deliver a secure, intuitive, and high‑performing product. This is a hands‑on role with full ownership of features — from development and testing through to deployment and user experience improvements. Your work will directly influence how millions of people communicate securely.
Responsibilities
- Lead development of key features from concept through release, taking full responsibility from early design discussions to testing and deployment.
- Build and improve the C.Email mobile application using React Native (Expo + CNG).
- Enhance app performance and stability; address bugs and UI issues.
- Integrate and optimise cryptographic components for performance.
- Produce modular, testable, and maintainable code with clear documentation.
- Create and maintain automated testing frameworks (unit, component, and user simulation).
- Work with blockchain engineers on integrations related to data backup and key management.
- Participate in daily stand‑ups and code reviews, contributing ideas and best practices.
Qualifications
- Extensive experience with React Native and TypeScript.
- Strong background in building automated test suites — unit, component, and user‑simulation.
- Solid understanding of mobile‑first architecture (local storage, offline‑first workflows).
- Experience in startups or small engineering teams (Series A/B or pre‑VC).
- Demonstrated ability to take ownership of product areas or features.
- Exposure to email protocols and standards (MIME, Gmail API) is beneficial.
Required Skills
- React Native (Expo) – advanced development and optimisation.
- Kotlin / Swift – for native modules.
- Go – used in cryptographic components.
- C++ – for performance and integration‑related tasks (secondary).
- GCP / AWS (basic) – setup and management of light infrastructure (SES, Lambda, Redis, RDS, EC2 autoscaling).
- Understanding of cryptographic concepts (key exchange, signing, encryption).
Preferred Skills
- Familiarity with email standards and protocols (e.g., MIME, Gmail API).
What’s Next?
- Talent Acquisition Interview (30–45 minutes) – an introductory call to learn about Certonymity’s mission and your background.
- Practical coding exercise (60–90 minutes) – a live coding session with our CTO and a Senior Engineer based on a task we’ll provide.
- Final Stage Interview (30 minutes) – meet our CEO and founder to discuss the role and company in more depth.
Senior Software Engineer in England employer: Certonymity
Contact Detail:
Certonymity Recruiting Team
StudySmarter Expert Advice 🤫
We think this is how you could land Senior Software Engineer in England
✨Tip Number 1
Get to know the company inside out! Research Certonymity's mission and products, especially C.Email. This will help you tailor your conversations and show that you're genuinely interested in what they do.
✨Tip Number 2
Practice your coding skills before the practical exercise. Brush up on React Native and TypeScript, and maybe even run through some common coding challenges. We want you to feel confident and ready to impress!
✨Tip Number 3
During interviews, don’t just talk about your past experiences; share how you can contribute to Certonymity’s goals. Highlight your ownership of projects and how you can enhance their encrypted email application.
✨Tip Number 4
Apply through our website! It’s the best way to ensure your application gets seen by the right people. Plus, it shows you’re proactive and keen to join our innovative team.
We think you need these skills to ace Senior Software Engineer in England
Some tips for your application 🫡
Show Your Passion: When writing your application, let your enthusiasm for secure communication technology shine through. We love candidates who are genuinely excited about what we do at Certonymity and can articulate how their skills align with our mission.
Tailor Your CV: Make sure to customise your CV to highlight your experience with React Native and TypeScript. We want to see how your background fits into the role of Senior Software Engineer, so don’t be shy about showcasing relevant projects or achievements.
Be Clear and Concise: Keep your application straightforward and to the point. We appreciate clarity, so avoid jargon and focus on what makes you a great fit for the team. Remember, we’re looking for someone who can communicate effectively, just like our product aims to do!
Apply Through Our Website: We encourage you to apply directly through our website. It’s the best way for us to receive your application and ensures you’re considered for the role. Plus, it shows you’re proactive and keen to join our innovative team!
How to prepare for a job interview at Certonymity
✨Know Your Tech Inside Out
Make sure you’re well-versed in React Native and TypeScript, as these are crucial for the role. Brush up on your knowledge of mobile-first architecture and cryptographic concepts, as you might be asked to explain how they apply to the development of secure communication tools.
✨Showcase Your Problem-Solving Skills
During the practical coding exercise, focus on demonstrating your thought process. Explain your approach to solving problems, especially when it comes to optimising app performance or addressing bugs. This will show Certonymity that you can think critically and take ownership of features.
✨Familiarise Yourself with Their Mission
Understand Certonymity’s goal of making encrypted email accessible. Be prepared to discuss how your experience aligns with their mission and how you can contribute to building a secure, user-friendly product like C.Email.
✨Prepare Questions for the Team
Have some thoughtful questions ready for your interviews, especially for the final stage with the CEO. Ask about the company culture, future projects, or how they envision the evolution of their technology. This shows your genuine interest in the role and the company.
