Principal Security Engineer

Principal Security Engineer 

London (Hybrid) | Technology & Engineering  | Permanent 

The Role

As a Principal Security Engineer at Capco, you'll lead hands-on security engineering delivery for clients across financial services and other complex environments. Depending on the engagement, you'll lead a technical workstream or operate independently as a Principal specialist. Your focus will span Application & Product Security, Cloud & Platform Security and DevSecOps, underpinned by strong security automation. You'll combine specialist depth with cross-domain judgement, client engagement and secure-by-design engineering. 

What You'll Do 

• Lead the design, implementation and technical assurance of secure solutions across applications, cloud platforms and delivery pipelines; remain hands-on with complex engineering and integration challenges. 

• Work directly with clients to understand requirements, lead technical workshops and shape practical security designs, delivery plans and technical proposals. 

• Embed security-by-design across applications, APIs, cloud workloads and the secure SDLC through threat modelling, CI/CD controls, SAST, SCA, DAST and container scanning. 

• Build and integrate scalable security automation using scripting, APIs, Infrastructure as Code and policy as code; improve control effectiveness and engineering workflows. 

• Lead technical workstreams or specialist assignments, assure engineering quality and operational handover, mentor engineers and develop reusable standards and patterns. 

• Leverage approved AI-enabled tools and automation to enhance security engineering efficiency and effectiveness, ensuring appropriate human oversight, security guardrails and validation. 

What We're Looking For 

• Proven hands-on security engineering delivery and technical leadership, including secure design decisions, engineering assurance, client engagement and mentoring. 

• Deep implementation expertise in one or more of Application & Product Security, Cloud & Platform Security or DevSecOps, with working knowledge of the other areas. 

• Practical experience securing applications, APIs, cloud workloads or engineering pipelines, supported by sound knowledge of threat modelling, vulnerability management and secure SDLC practices. 

• Experience with at least one major cloud platform (Azure, AWS or GCP) and cloud-native security principles, including an understanding of IaC, containers and workload identities. 

• Strong security automation capability with scripting, APIs and CI/CD tooling, plus experience with IaC or policy as code and integrating security tools into engineering workflows. 

• Broad awareness of network and infrastructure security, IAM, monitoring and data-protection controls; able to collaborate with specialists and explain technical trade-offs to clients. 

• Strong understanding of security standards and best practices, including ISO 27001, NIST and OWASP, with the ability to translate security requirements into practical engineering controls and solutions. 

Bonus Points For 

• Experience in financial services, energy or other regulated sectors; relevant certifications such as CISSP, CSSLP, CCSP or cloud security credentials. 
• Depth across multiple priority engineering domains; experience in software supply-chain or container security, technical presales, or security engineering for AI-enabled systems. 

Why Join Capco 

• Deliver high-impact security engineering solutions for leading financial institutions and other major clients. 

• Work in a collaborative, entrepreneurial consulting culture with continuous learning, training and certification opportunities 
• Help shape secure digital transformation across financial services and energy. 

Benefits 

We offer a competitive, people-first benefits package designed to support every aspect of your life: 

• Core Benefits: Discretionary bonus, competitive pension, health insurance, life insurance and critical illness cover.
• Mental Health: Easy access to CareFirst, Unmind, Aviva consultations, and in-house first aiders.
• Family-Friendly: Maternity, adoption, shared parental leave, plus paid leave for sickness, pregnancy loss, fertility treatment, menopause, and berea