Senior Application Security Engineer

This position is listed on behalf of a partner company, who manages all applications and next steps. Our partner is looking for a Senior Application Security Engineer based in Switzerland.

This is a senior application security opportunity within a globally distributed technology environment building products and infrastructure for the Web3 ecosystem. You will help protect applications trusted by millions of users, with a particular focus on digital assets, identities, decentralized applications, and blockchain technology. The role combines hands-on security engineering with threat modeling, secure design, vulnerability research, code reviews, and developer enablement. You will work closely with engineering and product teams to embed security throughout the software development lifecycle rather than addressing vulnerabilities only after release. Your work will directly influence the security posture, resilience, and trustworthiness of products operating at significant global scale. You will also contribute to security automation and AI-powered tooling as vulnerability detection and remediation techniques continue to evolve. This role is ideal for a proactive senior security engineer who enjoys technical depth, high autonomy, and solving complex security challenges alongside experienced engineering teams.

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Accountabilities

• Investigate vulnerabilities reported through the bug bounty program, determine their root cause and severity, and assess the appropriate remediation path.

• Collaborate with ethical hackers to triage security reports and work directly with product and engineering teams to resolve identified vulnerabilities.

• Document vulnerabilities clearly and precisely so engineering teams can understand, prioritize, and remediate issues efficiently.

• Write production-quality code to support security engineering initiatives and remediate vulnerabilities across client applications.

• Develop and contribute to AI-powered security tooling that supports vulnerability analysis, determination, and remediation as the threat landscape evolves.

• Assess potential vulnerabilities across applications and APIs and work with development teams to ensure remediation within established security SLAs.

• Support new product and feature development through security design reviews, threat modeling, security testing, and code reviews.

• Identify weaknesses and gaps in the secure software development lifecycle and proactively lead initiatives to strengthen security practices and controls.

• Validate security patches and fixes, including testing for potential bypasses or residual vulnerabilities.

• Develop automation, security controls, and developer education initiatives that reduce the likelihood of recurring vulnerabilities.

• Participate in security planning, roadmap discussions, team meetings, and cross-functional technical initiatives.

• Collaborate with engineering and product stakeholders to influence secure architectural and implementation decisions.

• Take ownership of security improvement initiatives and identify opportunities to make applications safer through innovative and practical solutions.

Requirements

• 6+ years of experience building and securing software, including substantial hands-on application or product security experience.

• Strong experience securing modern backend systems, web applications, and APIs.

• Proven experience with threat modeling, security architecture or design reviews, vulnerability assessments, and application security testing.

• Hands-on experience securing JavaScript-based applications across web and/or mobile environments, particularly Node.js, React, or React Native.

• Strong programming and coding skills, with the ability to work directly with software engineers to identify vulnerabilities and implement secure solutions.

• Solid understanding of modern web and mobile security principles, common attack vectors, exploitation techniques, and appropriate mitigations.

• Familiarity with blockchain technology, particularly Ethereum, decentralized applications, and cryptocurrency wallets.

• Strong communication and interpersonal skills, with the ability to influence technical decisions and collaborate effectively across distributed teams.

• Self-driven and proactive, with the ability to operate independently and take ownership in a high-autonomy remote environment.

• Strong problem-solving skills and a practical approach to identifying, prioritizing, and resolving security risks.

• Experience working as a software developer is a plus.

• Deep knowledge of Ethereum, other blockchain technologies, decentralized applications, and crypto wallets is advantageous.

• Knowledge of smart contract development and security is beneficial.

• Familiarity with AI-assisted security tooling or AI-powered vulnerability detection is an advantage.

• Experience using or contributing to relevant Web3 products or decentralized applications is a plus.

• Ability to work with some overlap across European and US-Pacific time zones.

• Alignment with a mission focused on building secure, accessible, and user-centric decentralized technologies.

Benefits

• Remote-first work: Join a fully distributed international team and work remotely.

• Flexible working arrangements: Benefit from an asynchronous working culture that provides flexibility around when and how you work.

• Global collaboration: Work with colleagues and technical experts across six continents.

• Competitive benefits package: Comprehensive benefits designed to support employees and their well-being.

• Equity: Receive an equity package that provides an opportunity to share in the organization's future success.

• Unlimited vacation: Flexible time off designed to support rest, recovery, and sustainable work-life balance.

• Company-wide recharge days: Dedicated zero-productivity days to disconnect and step away from work.

• Continuous learning: Access professional development opportunities through structured learning programs and extensive online courses.

• Career development: Build expertise alongside experienced technologists, security professionals, researchers, and builders within the global blockchain ecosystem.

• Web3 industry exposure: Work on security challenges at the intersection of application security, blockchain, decentralized applications, and emerging technologies.

• High-impact environment: Contribute directly to protecting products and infrastructure used by millions of users and developers worldwide.

• Autonomy and ownership: Shape your approach to improving application security and have meaningful influence over security initiatives and engineering practices.

\nHow Jobgether works:

We use an AI-powered matching process to ensure your application is reviewed quickly, objectively, and fairly against the role's core requirements. Our system identifies the top-fitting candidates, and this shortlist is then shared directly with the hiring company. The final decision and next steps (interviews, assessments) are managed by their internal team.

We appreciate your interest and wish you the best!

Why Apply Through Jobgether?

Data Privacy Notice: By submitting your application, you acknowledge that Jobgether will process your personal data to evaluate your candidacy and share relevant information with the hiring employer. This processing is based on legitimate interest and pre-contractual measures under applicable data protection laws (including GDPR). You may exercise your rights (access, rectification, erasure, objection) at any time.

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