CoreTech Security Services
Principal Systems Engineer

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About the Role
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 Responsibilities
As a Principal Systems Engineer, you may be:
- 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.
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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
Successful candidates will have strong experience in several of the following areas:
- 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.
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.
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.


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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.
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