Lead Application Security Engineer

Brunswick Group; Greater London; On-site; GBP 110,000 - 140,000; Full time

Job summary

Brunswick Group seeks a Lead Application Security Engineer to shape and mature its application security capability. You will provide senior security guidance across internally developed apps, cloud services, APIs, and AI-enabled workstreams, working with ICT and business stakeholders to balance risk with rapid delivery.

You will mentor teams, define guardrails, and oversee threat modelling, security reviews, and secure design patterns, with potential growth of the security function over time.

Qualifications

• 7+ years in cyber security, application security, DevSecOps, cloud security or related security role.
• Experience as senior technical advisor or lead in application security, DevSecOps, cloud security or secure engineering.
• Experience securing applications throughout the delivery lifecycle with software engineering/DevOps teams.
• Knowledge of secure development lifecycle, threat modelling, API security, authentication & authorization, dependencies, and remediation planning.
• Familiarity with AI-enabled technologies and associated risks is a plus.

Responsibilities

• Lead development of Brunswick's application security capability, including standards and guardrails.
• Advise ICT, AI Engineering, and stakeholders on security design decisions.
• Review designs, APIs, cloud services, and deployment patterns for security risks.
• Mature repeatable security reviews, threat modelling, and risk-based assurance.
• Guide secure development lifecycle practices and release security considerations.
• Conduct threat modelling for AI-enabled workflows and integrations.
• Support penetration testing and security testing activities.
• Document security requirements and remediation actions.

Skills

Security strategy

Threat modelling

DevSecOps

Cloud security

Security reviews

Education

Certifications: CISSP/CCSP/SSCP/CSSLP

Certifications: CISM/CISA/CRISC

Certifications: Security+ / CySA+ / CASP+

Tools

Azure

Entra ID

Key Vault

API Management

Job description

The Lead Application Security Engineer will join Brunswick's Information Security team and play a key role in shaping how the firm embeds security into application design, development, deployment, and technology change.

This is a senior individual contributor role initially, with scope to help establish and mature Brunswick's application security capability over time. The role will focus on providing risk-based security advice and assurance across internally developed applications, enterprise platforms, integrations, cloud services, SaaS solutions, and selected AI-enabled workstreams.

Working closely with ICT, AI Engineering, application owners, and business stakeholders, the Lead Application Security Engineer will help define practical security standards, guardrails, review processes, and secure design patterns that enable delivery teams to move at pace while managing risk appropriately.

About the Role

In this role, you will provide senior application security and DevSecOps expertise across technology projects, design reviews, cloud-based applications, APIs, integrations, delivery pipelines, and selected AI-enabled solutions.

You will act as a senior security advisor to technical and business teams, helping establish a repeatable application security model that can scale as demand grows, including the potential introduction of additional team members in the future.

Key responsibilities include:

• Lead the development of Brunswick's application security capability, including standards, secure design patterns, review processes, and practical guardrails.
• Act as a senior security advisor to ICT, AI Engineering, application owners, and business stakeholders.
• Review and assess application designs, architecture decisions, APIs, integrations, cloud services, and deployment patterns to identify security risks early in the delivery lifecycle.
• Mature repeatable approaches for application security reviews, threat modelling, and risk-based assurance across new and changed solutions.
• Provide guidance and oversight on secure development lifecycle practices, including security requirements, design review, code and security review considerations, dependency management, secrets management, testing, and release assurance.
• Conduct threat modelling for internally developed applications, AI-enabled workflows, integrations, automation use cases, and higher-risk technology changes, using STRIDE or similar methodologies.
• Advise on secure design principles, including identity and access management, API security, data protection, encryption, logging, monitoring, resilience, secure configuration, and least privilege.
• Support security review of CI/CD pipelines, infrastructure as code, containerised workloads, and cloud infrastructure, identifying practical controls for engineering and platform teams.
• Review and assess third‑party platforms, SaaS solutions, and new technology features, including AI‑enabled tools where there are material application, integration, or data security considerations.
• Support the development and application of secure patterns and guardrails for emerging technology adoption, including AI‑enabled solutions, agents, and automation where relevant.
• Support security assurance activities, including penetration testing, application security testing, remediation tracking, and ensuring appropriate logging, monitoring, and response considerations are built into new solutions.
• Define and document security requirements, architecture decisions, design recommendations, and risk‑based remediation actions.
• Support the future growth of the application security function, including helping define ways of working, capability needs, and technical guidance for future team members as the function matures.

What We're Looking For

We're looking for an experienced, technically capable security professional who can lead and mature an application security capability while remaining pragmatic, hands‑on, and delivery‑focused.

The ideal candidate will demonstrate:

• 7+ years' experience in cyber security, application security, DevSecOps, cloud security, security architecture, security engineering, or a related technical security role.
• Strong understanding of risk management and compensative controls.
• Experience operating as a senior technical advisor or lead within application security, DevSecOps, cloud security, secure engineering, or a related discipline.
• Proven experience working alongside software engineering, DevOps, platform, cloud, or ICT teams to secure applications and infrastructure throughout the delivery lifecycle.
• Strong understanding of secure development lifecycle and application security practices, including threat modelling, secure design, API security, authentication and authorisation, secrets management, dependency management, security testing, and remediation planning.
• Practical experience reviewing application architectures, APIs, integrations, cloud services, CI/CD pipelines, containerised workloads, or infrastructure as code.
• Practical understanding of Microsoft 365, Azure, SaaS platforms, and Azure application security controls such as Entra ID, managed identities, Key Vault, API Management, container security, logging, monitoring, and secure configuration.
• Experience conducting STRIDE‑based threat modelling, technical risk assessments, application security reviews, or security design reviews.
• Experience developing security standards, secure design patterns, review processes, or guardrails that can be adopted by engineering and delivery teams.
• Ability to translate technical security risks into clear, business‑focused recommendations and influence delivery teams without directly owning implementation.
• Familiarity with AI‑related technologies, large language models, AI‑enabled applications, and associated risks such as data exposure, prompt injection, insecure integrations, and excessive agent permissions would be beneficial.
• Strong written and verbal communication skills, sound judgement, attention to detail, and the ability to balance security requirements with business needs.
• Experience working in an ISO27001‑aligned or regulated environment would be beneficial.
• Preferred, but not essential, certifications:
• ISC2: CISSP, CCSP, SSCP, CSSLP
• ISACA: CISM, CISA, CRISC
• CompTIA: Security+, CySA+, CASP+
• GIAC, Microsoft Azure, or other relevant application security, cloud security, architecture, or DevSecOps certifications

Why Join Us

Joining Brunswick unlocks a range of employee benefits to support your financial future, health and wellness, family and community, and continuous professional development.

About Brunswick

Brunswick is a global advisory firm. We help companies tackle high‑stakes issues, navigate complex stakeholder relationships, and deliver high‑impact outcomes.

Our clients value our ability to anticipate, shape, and respond to the key players and forces in the financial and investment arena, regulatory and geopolitical universe, NGO community, workforce and beyond. They rely on us for deep experience, fresh perspectives and original thinking. So, in Brunswick you will find an exceptional range of experience and talent with a rich mix of backgrounds. From the beginning, we have prioritized attracting, developing, and retaining the best professionals in the industry, united by a culture of inclusivity, excellence, and intellectual curiosity.

Founded in 1987 in London, the firm has organically grown to 27 offices in 18 countries across the Americas, Europe, Middle East, Africa, Asia and Australia. We operate as a “one‑firm firm” with no individual profit centers. This allows us to assemble fully integrated, bespoke teams for each client, able to draw on the full resources of Brunswick anywhere in the world.

Brunswick is an equal opportunity employer. All qualified applicants will be considered without regard to race, religion, color, national origin, gender, sexual orientation, age, disability, pregnancy, genetic information, or any other status protected by applicable law. Pleaseread our Global Privacy Notice to understand how your data is managed.