Security Engineer

About Yousign Yousign (soon to be Youtrust) is a European Digital Trust provider, fully compliant with eIDAS and the highest European standards. Our three modules – electronic signatures, identity and document verification, and e-seals – can be used independently or combined within sector-specific workflows, ensuring simple, secure and legally compliant processes for SMEs and mid‑sized companies.

Hosted and processed entirely in Europe, we guarantee sovereignty, transparency and reliability. As a certified B‑Corp, we combine innovation with responsibility – building trust at the heart of every digital exchange.

We are entering a key moment as we expand from eSignature to the full Digital Trust chain.

Your Role As a Security Engineer at the company, you are the embedded security partner for the entire company, with Product as your primary internal client. You lead the company's security review cycle end‑to‑end on prioritized initiatives: from understanding the context of a new feature or project, to issuing your requirements and guidance, supporting implementation, and unblocking through risk management when needed.

You own and operate the pentest and Bug Bounty programs and ensure consistent, pragmatic security coverage across all team initiatives, from Engineering and Product to cross‑functional projects company‑wide.

You also step into the topics that make the company a Digital Trust provider: the security of our Trusted Zone, our fraud detection and prevention efforts, and our regulatory compliance (eIDAS, NIS2, ISO 27001). You won't own every one of these, but you contribute wherever the team needs you — your specialization defines where you spend most of your time, not a silo you stay inside.

• Lead the end-to-end security review cycle for all product features: context intake, Decision Records, implementation support, and risk‑based unblocking.

• Own and operate the company's Bug Bounty program: triage reports, drive remediation, and manage reward decisions.

• Identify, prioritise, and track remediation of vulnerabilities across the company's product and infrastructure perimeter.

• Contribute to the security of the Trusted Zone, and to fraud detection and prevention, alongside the Security & Compliance team.

• Support regulatory compliance (eIDAS, NIS2, ISO 27001): help translate requirements into technical controls, and contribute to audits and remediation when needed.

• Extend security expertise beyond Product to all company initiatives: assess risks, issue guidance, and maintain a consistent security posture company‑wide.

• Take part in the team's weekly on‑call ("doctor") rotation, and build automation (n8n, AI tooling, alerting) to reduce manual toil.

• Raise the security bar across Engineering and beyond: share knowledge, coach teams on secure‑by‑design practices, and build security awareness.

• You have deep, hands‑on expertise in web application and API security, you know attack and defense mechanisms inside out and can spot a vulnerability in a PR or architecture diagram.

• You are able to independently run threat modeling sessions, produce clear Decision Records, and translate security risks into actionable requirements for engineering teams.

• You have experience managing vulnerabilities across a product perimeter: triaging, prioritising, tracking remediation, and knowing when to accept risk versus escape.

• You have participated in or run Bug Bounty programs. You understand triage workflows, reward logic, and how to communicate decisions clearly to researchers.

• You use AI actively to automate parts of your security work, CVE monitoring, Bug Bounty triage, report generation, and you think critically about how to integrate AI into existing workflows rather than simply adding…