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For Companies At a Glance
- Tasks: Lead the design and support of high-security systems for defence and aerospace.
- Company: Join Leonardo, a global leader in Aerospace, Defence, and Security.
- Benefits: Enjoy flexible working, generous leave, and a comprehensive benefits package.
- Other info: Be part of an inclusive team that values diversity and innovation.
- Why this job: Make a real impact in a critical role while advancing your career.
- Qualifications: Expertise in Windows-based infrastructures and security compliance required.
The predicted salary is between 60000 - 80000 £ per year.
Your Impact
Leonardo is looking for a 3rd Line Platform Engineer to join our collaborative and skilled team supporting a critical MOD site. This is an exciting opportunity to serve as a Subject Matter Expert (SME) in Windows-based enterprise infrastructures. You'll play a central role in the design, deployment, and support of high-security systems that underpin key defence and aerospace operations. This role is based full-time on site in London and requires DV clearance.
What you will do as a Principal Platform Engineer:
- Take ownership of complex technical issues through to resolution, collaborating with users and other IT teams.
- Provide expert-level troubleshooting for incidents escalated from 1st and 2nd line support, ensuring consistent and minimal disruption to services.
- Deploy and integrate secure Windows Server environments (Active Directory, Group Policy, DNS, DHCP) using industry best practices.
- Implement and maintain infrastructure security measures such as patching, access controls, and hardening to align with compliance and internal governance.
- Use monitoring tools to proactively optimize system performance and ensure high availability.
- Create and maintain detailed technical documentation and contribute to internal knowledge sharing and mentoring.
- Participate in IT projects, ensuring infrastructure design meets both technical and business objectives.
- Collaborate closely with network, security, and application teams to deliver reliable, secure IT services.
What you’ll bring:
- Proficiency in Ivanti Application & Device Control or similar lockdown tools.
- Experience working with high-security MOD systems and secure design principles.
- Familiarity with security and compliance documentation (e.g. RMADS, SyOPs, NIST frameworks).
Core Technologies
- Microsoft: Windows Server 2019/2022/2025, Active Directory, Group Policy, DNS, DHCP, Exchange Server 2019, SQL Server, SharePoint 2019
- VMware: VMware Cloud Foundation, vSphere, ESXi, NSXT, and vSAN
- Endpoint & Configuration: Windows 10 & 11, Microsoft Endpoint Configuration Manager (MECM)
- Monitoring & Observability: Microsoft System Centre Operations Manager (SCOM)
- PKI Technologies: Microsoft Certificate Services, Hardware Security Modules (HSMs), and lifecycle key management
Security Clearance
This role is subject to pre-employment screening in line with the UK Government’s Baseline Personnel Security Standard (BPSS). An additional range of Personnel Security Controls referred to as National Security Vetting (NSV) may apply, this could include meeting the eligibility requirements for The Security Check (SC) or Developed Vetting (DV).
Why join us
At Leonardo, our people are at the heart of everything we do. We offer a comprehensive, company-funded benefits package that supports your wellbeing, career development, and work–life balance. Whether you're looking to grow professionally, care for your health, or plan for the future, we’re here to help you thrive.
- Time to Recharge: Enjoy generous leave with the opportunity to accrue up to 12 additional flexi-days each year.
- Secure your Future: Benefit from our award-winning pension scheme with up to 15% employer contribution.
- Your Wellbeing Matters: Free access to mental health support, financial advice, and employee-led networks championing inclusion and diversity.
- Rewarding Performance: All employees at management level and below are eligible for our bonus scheme.
- Never Stop Learning: Free access to 4,000+ online courses via Coursera and LinkedIn Learning.
- Refer a friend: Receive a financial reward through our referral programme.
- Tailored Perks: Spend up to £500 annually on flexible benefits including private healthcare, dental, family cover, tech & lifestyle discounts, gym memberships and more.
- Flexible working: Flexible hours with hybrid working options. For part time opportunities, please talk to us about what might be possible for this role.
Leonardo is a global leader in Aerospace, Defence, and Security. Headquartered in Italy, we employ over 53,000 people worldwide including 8,500 across 9 sites in the UK. Our employees are not just part of a team—they are key contributors to shaping innovation, advancing technology, and enhancing global safety. At Leonardo we are committed to building an inclusive, accessible, and welcoming workplace. We believe that a diverse workforce sparks creativity, drives innovation, and leads to better outcomes for our people and our customers. If you have any accessibility requirements to support you during the recruitment process, just let us know. Be part of something bigger - apply now!
Principal Platform Engineer in London employer: Leonardo
Contact Detail:
Leonardo Recruiting Team
StudySmarter Expert Advice 🤫
We think this is how you could land Principal Platform Engineer in London
✨Tip Number 1
Network like a pro! Reach out to current employees at Leonardo on LinkedIn or through mutual connections. A friendly chat can give you insider info and might just get your foot in the door.
✨Tip Number 2
Prepare for the interview by brushing up on your technical skills and understanding the specific technologies mentioned in the job description. We want to see you shine as a Subject Matter Expert!
✨Tip Number 3
Showcase your problem-solving skills during interviews. Be ready to discuss past experiences where you took ownership of complex issues and how you resolved them. We love a good story!
✨Tip Number 4
Don’t forget to apply through our website! It’s the best way to ensure your application gets seen by the right people. Plus, it shows you’re genuinely interested in joining our team.
We think you need these skills to ace Principal Platform Engineer in London
Some tips for your application 🫡
Tailor Your CV: Make sure your CV reflects the skills and experiences that match the Principal Platform Engineer role. Highlight your expertise in Windows-based enterprise infrastructures and any relevant security clearance experience.
Craft a Compelling Cover Letter: Use your cover letter to tell us why you're the perfect fit for this role. Share specific examples of how you've tackled complex technical issues and collaborated with teams in high-security environments.
Showcase Your Technical Skills: Don’t forget to mention your proficiency with core technologies like Windows Server, Active Directory, and monitoring tools. We want to see how you can contribute to our team right from the start!
Apply Through Our Website: For the best chance of success, make sure to apply directly through our website. This way, we can easily track your application and get back to you quicker!
How to prepare for a job interview at Leonardo
✨Know Your Tech Inside Out
As a Principal Platform Engineer, you'll need to demonstrate your expertise in Windows Server environments and related technologies. Brush up on Active Directory, Group Policy, and security compliance documentation like RMADS and NIST frameworks. Be ready to discuss how you've applied these in past roles.
✨Showcase Problem-Solving Skills
Expect to face complex technical issues during the interview. Prepare examples of how you've taken ownership of such challenges, collaborating with teams to resolve them. Highlight your troubleshooting experience, especially with high-security MOD systems, to show you're the right fit for the role.
✨Emphasise Collaboration
This role requires close collaboration with various teams. Be prepared to discuss how you've worked with network, security, and application teams in the past. Share specific instances where your teamwork led to successful project outcomes or improved system performance.
✨Prepare Questions About the Role
Interviews are a two-way street! Prepare thoughtful questions about the team dynamics, ongoing projects, and the company's approach to security and compliance. This shows your genuine interest in the role and helps you assess if it's the right fit for you.