Senior Principal Engineer- M365 Infrastructure, Security and Messaging

Job Purpose:

The Senior Principal Engineer will lead the design, development, and implementation of next-generation solutions across Messaging (Exchange Online, Proofpoint), M365 Security components, and office M365 infrastructure. This position plays a critical role in ensuring seamless demand intake from product capability teams into the engineering portfolio, enhancing security posture, and architecting scalable, compliant, and resilient infrastructure solutions across M365.

Key Responsibilities

• Messaging Architecture:
  Lead end-to-end design and engineering of Exchange Online and Proofpoint to ensure reliable messaging services.

• Security Posture Enhancement:
  Strengthen M365 security capabilities tied to email and infrastructure services, addressing regulatory and organizational needs.

• Infrastructure Strategy:
  Architect future-ready solutions across Office and M365 infrastructure to optimize scalability and performance.

• Compliance & Reliability:
  Ensure platforms meet all regulatory, security, and performance standards to minimize risks and disruptions.

• Stakeholder Collaboration:
  Collaborate with product teams, operations, and external vendors to deliver impactful solutions aligned with business objectives.

• Demand Intake & Portfolio Alignment:
  Streamline engineering intake processes for efficient alignment with the M365 portfolio strategy.

• Change & Release Management:
  Oversee the compliant deployment of infrastructure changes while minimizing risks to operations.

• Technical Debt Management:
  Identify and remediate legacy architecture and vulnerabilities to improve overall platform health.

• Innovation & Optimization:
  Drive automation, modernization, and efficiency improvements across infrastructure layers.

• Leadership & Mentorship:
  Provide technical guidance to engineering teams and foster cross-functional collaboration across Core Tech.

• Problem Solving & Innovation

The Senior Principal Engineer is responsible for addressing complex infrastructure and security challenges, anticipating future needs, and designing resilient systems to elevate user experience across GSK's enterprise landscape.

Required Skills & Qualifications:

• 15 to 18 years of professional experience with bachelor's or master's degree in computer science or a related field

• 10+ years of experience in infrastructure and operations.

• 8+ years in overall M365 infrastructure, messaging and security.

• 4+ years in engineering and architecture roles.

• Expertise in security, network, and record retention requirements.

• Experience managing both on-premise and cloud-hosted solutions.

• Proficiency in automation workflows across enterprise services.

• Knowledge of industry best practices for real-time monitoring across large-scale networks.

• Strong communication skills for effective collaboration with technical and business teams.

• Proven track record of tactical execution in regulated environments.

• Hands-on experience with Agile methodologies (e.g., SAFe) and IT Service Management (ITSM).

• Experience engaging distributed teams across multiple time zones

• Experience in Agentic AI tools is desired

Inclusion at GSK:

As an employer committed to Inclusion, we encourage you to reach out if you need any adjustments during the recruitment process.

Please contact our Recruitment Team at IN.recruitment- to discuss your needs.

Why GSK?

Uniting science, technology and talent to get ahead of disease together.

GSK is a global biopharma company with a purpose to unite science, technology and talent to get ahead of disease together. We aim to positively impact the health of 2.5 billion people by the end of the decade, as a successful, growing company where people can thrive. We get ahead of disease by preventing and treating it with innovation in specialty medicines and vaccines. We focus on four therapeutic areas: respiratory, immunology and inflammation; oncology; HIV; and infectious diseases – to impact health at scale.

People and patients around the world count on the medicines and vaccines we make, so we're committed to creating an environment where our people can thrive and focus on what matters most. Our culture of being ambitious for patients, accountable for impact and doing the right thing is the foundation for how, together, we deliver for patients, shareholders and our people.

Inclusion at GSK:

As an employer committed to Inclusion, we encourage you to reach out if you need any adjustments during the recruitment process.

Please contact our Recruitment Team at IN.recruitment- to discuss your needs.

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