Principal Systems Engineer responsible for architecting complex multidisciplinary systems across software, hardware, networks, and third-party technologies. The role covers requirements engineering, system architecture, interface management, technical trade-offs, integration, verification, validation, customer acceptance, and technical risk management. The engineer will act as technical authority on major projects, lead engineering practices, mentor colleagues, and maintain hands-on involvement throughout delivery.
Our Software Engineering team develops bespoke capabilities for clients in the Cyber Security domain. We may be building assured products that prioritise engineering rigour and reliability, rapid solutions that bring together existing tooling for high-impact results, or blended operational systems that combine software, hardware, networks and third-party technologies to address real-world challenges in the field.
Common to all is a commitment to technically led decisions, meaningful technical challenge, and seeing our work make it off the shelf and into the hands of our customers.
As our projects increasingly bring together multiple technologies and engineering disciplines, we are looking for a Principal Systems Engineer, operating as the systems architect and cross-discipline technical authority on our larger projects, to take technical ownership of complete systems from early concept through delivery and acceptance. This role may suit an experienced Systems Architect, Lead Systems Engineer or Technical Authority who wants to remain closely involved throughout integration and delivery. There is also opportunity to grow the scope of this role to encompass the professionalisation of engineering across multiple projects and teams.
This role is about making sure we build the **right system**, not simply building individual components well. You will work with customers and engineers to understand operational problems, establish system requirements and architecture, make informed technical trade-offs, manage interfaces and guide systems through integration, verification and validation.
You will be equally comfortable discussing a customer's operational need, reviewing a software or network architecture, understanding the constraints imposed by a hardware component, and deciding how the complete system can be demonstrated to meet its requirements.
We're led by engineers and empowered to optimise our lightweight engineering processes with the knowledge gained from each project. We are not looking to introduce process for its own sake; we want systems engineering practices that help teams make better technical decisions, expose problems early and deliver dependable capability.
We are ideally looking for a candidate who holds an active Security Clearance to join our team; however, we will consider sponsoring new clearances for candidates who meet our technical requirements.
Key Responsibilties
- Working with customers and engineering teams to turn operational needs into clear system objectives, requirements and acceptance criteria.
- Defining system architectures, boundaries and interfaces across software, hardware, networks, infrastructure and third-party technologies.
- Leading technical trade-offs, balancing performance, security, risk, complexity and delivery constraints.
- Defining integration, verification and validation strategies and providing technical leadership through system integration and acceptance.
- Acting as technical authority for multidisciplinary projects, managing technical risks and helping establish pragmatic systems engineering practices across Software Engineering.
As a Principal Systems Engineer, you may be:
This is a hands-on technical leadership role. You will typically work closely with small engineering teams rather than operating as a separate governance function.
You will also help establish pragmatic systems engineering practices across Software Engineering, mentoring colleagues and identifying where additional rigour provides genuine engineering value.
Desirable Skills
- Designing and delivering complex systems involving multiple interacting technologies or engineering disciplines.
- Requirements engineering, system architecture, functional decomposition and interface management.
- Planning and leading system integration, verification, validation and customer acceptance activities.
- Evaluating technical options and communicating engineering trade-offs covering areas such as performance, reliability, security, maintainability, cost and delivery risk.
- Technical leadership within multidisciplinary teams, ideally in domains such as defence, cyber security, communications, aerospace, robotics or other complex systems environments.
Successful candidates will have strong experience in several of the following areas:
Familiarity with systems modelling, architecture frameworks, SysML, requirements management tools or MBSE approaches is useful, but practical systems thinking is more important than experience with a particular methodology or tool.
This vacancy is for an experienced technical leader who enjoys understanding the complete problem, bringing structure to ambiguity and helping multidisciplinary engineering teams turn individual technologies into coherent, dependable systems.
Work Benefits
- Promotions are based on technical excellence and reviewed regularly.
- 25 days holiday per year (with bank holidays on top), option to buy up to 5 days per year.
- Level up with an extra day of holiday per year, up to an extra 5 days, starting from 2 years' service.
- We offer financial support to cover HMRC allowable costs of relocating if you’re moving to the area.
- Training and development opportunities to support your career aspirations
- O'Reilly books subscription which provides access to huge range of technical books
- Regular events including internal technical conferences, company socials and pizza-fuelled lunchtime seminars.
- Free seasonal fruit, tea, coffee, milk, squash and hot chocolate.
Health Benefits - Private medical including access to
- Private online GP, and a helpline to speak with various healthcare professionals.
- Physiotherapists, osteopaths or chiropractors for muscle, bone, and joint pain.
- Mental health - counselling, and specialist consultations and treatment with psychologists and cognitive behavioural therapists.
- Annual Health assessment.
Financial Benefits
- A company bonus scheme so that everybody is rewarded for company success. This is an annual award that is based on the company hitting its targeted forecast. We have achieved this every year to date.
- 8% company contribution to pension with no minimum requirement for employee contribution.
- Death in Service cover of 4x base salary.
Lifestyle Benefits
- Enhanced maternity/paternity/adoption leave: 12 weeks maternity leave at full pay as soon as you join, further enhanced to 20 weeks full pay from 2 years’ service. 2 weeks paternity leave at full pay as soon as you join, further enhanced to 4 weeks full pay from 2 years’ service.
- Enhanced cycle-to-work scheme including the ability to purchase a bike over £1,000 (e-bikes, specialist cycles and trikes allowed).
Salary
We're open to hiring Senior Engineers ready to take the step up to Principal or already established Principal Engineers, salary will be reflected on experience. We will have candid discussions around the package on offer in our initial conversations so you can know what to expect should you receive an offer from us.
Location
We are based in the centre of Cheltenham in a stunning new build contemporary office, 5 minutes walk from the local shops and cafes.
Additional Details
Our interview process is quick and to the point: if you look like a good fit for the role, we'll schedule a brief call to discuss it in more detail and answer any questions you may have. If that goes well, we'll arrange a technical interview to understand your level of experience. We aim to get back to you with an answer within a couple of days of the technical interview.
Please note, due to sensitivity of the role, successful applicants must be eligible and willing to undergo (or already hold) SC clearance.
If you’re looking for a challenging role where you can make a real impact in the world, in a friendly environment and with all the support to advance your career, click apply.
Similar Jobs
Professional Services • Security • Defense • Industrial
Leads systems engineering for complex defense and cybersecurity projects, owning requirements, architecture, technical solutions, lifecycle processes, reviews, risk, compliance, suppliers, and customer acceptance. Provides technical direction across hardware, firmware, and software disciplines; manages systems engineering teams; serves as design authority; supports bids, security compliance, recruitment, mentoring, and line management.
Top Skills:
Embedded SystemsFirmwareHardwareIncoseIso 15288Iso/Ieee/Iec StandardsNcsc Security ProcessesRequirements Management ToolsSoftwareSystems Modeling Tools
Aerospace • Artificial Intelligence • Cloud • Machine Learning • Software • Cybersecurity • Defense
Provides technical leadership for embedded application software supporting aircraft engine controls. Responsibilities include software architecture, engine control algorithm development, hardware/software integration, verification, certification, cybersecurity design review, safety assessment, design review approval, process improvement, and technical communication with internal teams, customers, and regulators. The role requires extensive embedded software experience and expertise with DO-178C and ARP4754 certification processes.
Top Skills:
Arp4754Do-178CEmbedded Software
Aerospace • Security • Software
Lead the architecture, design, requirements management, integration, verification, validation, qualification, and lifecycle governance of safety-critical mission computing systems for military aircraft. Serve as a design authority and technical decision maker, lead multidisciplinary engineering teams, approve technical documentation, resolve customer challenges, and support bid development and solution shaping.
Top Skills:
Ai/MlDoorsMbsePtc ModelerRhapsody
What you need to know about the London Tech Scene
London isn't just a hub for established businesses; it's also a nursery for innovation. Boasting one of the most recognized fintech ecosystems in Europe, attracting billions in investments each year, London's success has made it a go-to destination for startups looking to make their mark. Top U.K. companies like Hoptin, Moneybox and Marshmallow have already made the city their base — yet fintech is just the beginning. From healthtech to renewable energy to cybersecurity and beyond, the city's startups are breaking new ground across a range of industries.
