Senior Security Architect

About Expleo and the service

Role scope

Architecture, risk, and assurance

• Produce and maintain high- and low-level security architecture and design documentation for the client security tooling estate for approval by the UK Head of Service.
• Review architecture and risk for proposed high-risk firewall, intrusion prevention, gateway, privileged access, and application control changes before Change Advisory Board review.
• Define logging and audit requirements, including log sources, SIEM feed requirements, and retention architecture aligned with client policy and regulation.
• Assess and recommend tooling and approaches for PKI and secrets management.
• Produce NIS Regulations and NCSC CAF alignment assessments and contribute evidence to regulatory reporting.
• Develop risk treatment plans and maintain security risk register inputs; prepare GRC reporting inputs and governance-board technical content and risk papers.
• Maintain the master security architecture diagrams and ensure engineering team diagrams are consistent and up to date.

Improvement and technical leadership

• Identify and assess improvement opportunities, including benefit-cost appraisal and sequencing quick wins, foundational change, and strategic uplift.
• Consider operational technology and IT/OT boundary risk in architecture and design work.
• Provide technical leadership, peer review, and mentoring to the Lead Security Engineer, Security Engineers, and Vulnerability and Patch Manager.
• Support Cybersecurity Practice growth through knowledge sharing, technical contribution, and client-facing delivery.

Education, certification, and experience

• Degree in computer science, cybersecurity, information systems, or a related discipline, or equivalent professional experience.
• At least one of CISSP, CISSP-ISSAP, or SABSA Chartered Foundation is required.
• At least 12 years in IT and cybersecurity, including at least 6 years in security architecture for enterprise or CNI environments.
• Experience producing architecture, design, and risk artefacts for regulated organizations; supporting governance boards, risk registers, and GRC reporting; and working with multi-supplier environments and managed security providers.

Essential technical and professional skills

• Enterprise security architecture across network, identity, endpoint, cloud, and data security domains.
• Designing logging and SIEM integration architectures, including log-source definition and retention requirements.
• Applying risk assessment methods such as ISO/IEC 27005 and NIST SP 800-30.
• Working knowledge of the NIS Regulations, NCSC CAF, ISO/IEC 27001, NIST CSF, and CIS Controls.
• Reviewing proposed changes for architectural and security risk and producing clear, evidence-based recommendations.
• Excellent written communication for executive, governance, and regulator-facing documentation; ability to lead and quality-assure other engineers’ work.

Advantageous qualifications and experience

• TOGAF, a cloud security certification such as CCSP, AZ-500, or AWS Security Specialty, or GICSP/ISA/IEC 62443 certification is advantageous.
• Energy, utilities, or other CNI experience; OT/ICS security, Purdue model, and IEC 62443 knowledge; GRC tools such as ServiceNow IRM or Archer; and Ofgem or NIS-regulated assurance experience are desired.

Work arrangements and eligibility

• Applicants must have the right to work in India and be based in or willing to relocate to Chennai.
• Applicants must complete enhanced pre-employment background screening equivalent in standard to the UK Baseline Personnel Security Standard and any additional client vetting.
• The role requires hours overlapping with the UK business day, with occasional out-of-hours advisory support during major incidents.
• Excellent written and spoken English is required for engagement with senior UK stakeholders.
• Applicants must be comfortable working within a strict security boundary without access to client operational systems or data.

Benefits

• Expleo describes a collaborative environment, opportunities to develop skills, and accredited training through Expleo Academy.
• Competitive local company benefits are noted, with the India benefits package to be confirmed.