Application Security Engineering Manager

About the role

Synthesia’s engineering and research organisation is scaling rapidly, increasing the complexity of securing its AI‑native products. The Application Security team is tasked with building security tooling, embedding security into the development lifecycle, and enabling a small, highly capable team to punch above its weight. We are looking for an Engineering Manager to lead and grow this AppSec team, working closely with senior engineers on threat modelling, security tooling, and AI‑assisted development security.

Key responsibilities

• Lead, support, and grow a team of senior and staff‑level security engineers, owning hiring, onboarding, performance management and career development.
• Define and own the AppSec strategy and roadmap, translating business risk and engineering context into a prioritized programme with measurable outcomes.
• Act as a technical partner, engaging deeply on threat models, security architecture, agentic tooling design and risk decisions.
• Maintain the team’s operating rhythm (OKRs, quarterly planning, cross‑team coordination) and communicate with leadership.
• Represent AppSec externally with customers, auditors and compliance programmes such as SOC2 and ISO42001.

Required profile

• Security engineer who has progressed into leadership, comfortable rolling up sleeves while providing organisational direction.
• Strong communicator able to discuss technical details with senior engineers and frame risk for leadership.
• Proven people‑management experience hiring, growing and performance‑managing senior security engineers.
• Experience leading an AppSec programme in a fast‑growing SaaS or AI company.
• Deep understanding of AI‑native security challenges, including LLM‑driven attack surfaces.

Required skills

• Python
• JavaScript
• AWS and/or GCP cloud infrastructure
• GitHub Actions
• Threat modelling and secure design review
• AI‑SAST / SCA tooling, vulnerability management, security automation
• Kubernetes (operational/security perspective)
• Familiarity with tools such as Semgrep, Wiz, CrowdStrike, HackerOne, Claude Code, Cursor, StepSecurity

What we offer

• Flexible, remote‑friendly role based in Europe or London hybrid.
• 25 days of annual leave plus local public holidays.
• Generous referral scheme and work‑from‑home setup.
• Up to 60 days per year of remote work from anywhere.
• Significant career growth opportunities shaping a market‑defining AI video platform.