Software Developer

Open 35d
This position is no longer accepting applications(closed Jul 24, 2026).

Successful candidate must hold a minimum of SC clearance and be willing to undergo DV (Developed Vetting) clearance. More information can be found here - National security vetting: clearance levels - GOV.UK ()

Our client, a leading consultancy in the Defence & Security sector, is currently seeking an experienced Software Developer to join their team on a permanent basis, based in Leatherhead.

Key Responsibilities:
  • Design, develop, and maintain high-quality software components using Java and C++, with a focus on robustness, performance, and maintainability
  • Implement and extend code that interacts with a flexible integration framework for solver coupling and data exchange
  • Work closely with clients, domain scientists, and computational engineers-often on-site-to understand requirements and translate them into effective software solutions
  • Contribute to defining and evolving software architecture, balancing performance, scalability, and long-term maintainability
  • Write clean, well-documented, and testable code in line with scientific software development best practices
  • Participate regularly in code reviews, debugging sessions, and performance profiling to improve code quality across the team
  • Support and mentor junior developers through technical guidance, constructive review, and knowledge sharing
  • Over time, take on increasing responsibility for guiding technical direction and contributing to the planning, delivery and management of project work
  • Help develop client relationships and contribute to development of new business, such as through writing effective proposals
  • Thrive in a consultancy environment solving real-world, high-consequence challenges
Job Requirements:
  • Professional experience developing software in Java and C++
  • Practical experience applying object-oriented design principles and modular software architectures
  • Familiarity with collaborative development practices, including Git and CI/CD pipelines
  • Experience working across the full software development lifecycle, including design, implementation, testing, and maintenance
  • Knowledge of software testing techniques and a commitment to writing reliable, maintainable code
  • Solid analytical and problem-solving skills, with the ability to work effectively both independently and as part of a multidisciplinary team
  • The confidence and communication skills to work directly with clients and technical stakeholders
  • Sole UK nationality, due to the nature of the work
Desirable Skills:
  • Experience writing unit tests using JUnit and Google Test Frameworks
  • Solid understanding of numerical methods and scientific computing principles
  • Background in physics, applied mathematics, or engineering
  • Experience in development with Fortran 90
  • Experience in SQL database development
  • Experience using the Java Spring framework
  • Experience working in the defence sector
Benefits:
  • Competitive salary with yearly reviews
  • 25 days holiday + the opportunity to buy 5 days
  • A company with its heart in the right place and a welcoming work culture
  • Happy to talk flexible working
  • Enhanced parental benefits
  • Company pension scheme
  • Targeted professional development
  • Life assurance
  • Private healthcare membership
  • Bonus scheme linked to company performance
  • Paid membership fees to a professional institution
  • Support in attaining professional membership
  • Cycle to work scheme
  • Season rail ticket loan
  • Additional optional benefits tailored to your personal requirements


If you are an experienced Software Developer seeking a new challenge and wish to further develop your technical and leadership skills, we would love to hear from you. Apply now to join our client's impactful and dynamic team.