Senior C++ Software Engineer in London

Are you passionate about engineering? Do you want to make a difference? ALTEN is a global engineering and technology consultancy operating across over 30 countries worldwide. We partner with industry leaders across sectors including Aeronautics, Aerospace, Defence, Naval, Automotive, Energy, Rail, and many more to deliver innovative engineering solutions that drive technological advancement and support sustainable transformation. Our teams of passionate and agile engineers work on cutting‐edge projects that shape the future of technology and sustainability. At ALTEN, we empower talented engineers to innovate, solve complex challenges, and deliver impactful solutions that build tomorrow's world today.

Join our team to deliver high‐impact Defence software solutions for mission‐critical systems. You'll work on projects requiring robust, safety‐regulated software development, applying your expertise in C++ and compliance standards to ensure reliability and security. This is an opportunity to contribute to fast‐paced defence programmes, where your work directly supports operational capability.

Location: London (EC2)

Work Arrangement: Hybrid (3 days per week)

Seniority: Senior (8+ years of experience)

Clearance: SC Clearance

Key Responsibilities:

• Design, develop, and maintain C++ software for mission‐critical defence systems.
• Apply DO‐178 principles and ensure compliance with safety standards.
• Perform black‐box/system‐level testing and verification activities.
• Collaborate with multi‐disciplinary teams to integrate software into complex systems.
• Support configuration management and CI/CD processes (Git, Jenkins, CMake).
• Produce clear technical documentation aligned with regulated environments.

Required Skills:

• 8+ years of proven experience in C++ (modern standards: C++11/14/17/20).
• Knowledge of DO‐178 processes and safety‐critical development.
• Experience with black‐box testing, verification, and requirements traceability.
• Familiarity with configuration management and build tools (Git, Jenkins, CMake).
• Understanding of coding standards (e.g., MISRA, CERT C++).

Soft Skills & Collaboration:

• Excellent communication skills for cross‐functional collaboration.
• Strong problem‐solving and adaptability in regulated environments.
• Ability to work effectively in multi‐disciplinary teams.
• Proactive approach to continuous improvement and quality assurance.

Required Qualifications:

• Bachelors or Masters degree in Software Engineering, Computer Science, or related discipline OR relevant technical military background with equivalent experience.
• Must be eligible to hold or already hold UK SC Security Clearance.

Desirable Skills:

• Exposure to RTOS, Linux, or embedded systems.
• Familiarity with requirements tools (e.g., DOORS).
• Background in defence, aerospace, or safety‐critical domains.

We foster a community of dually talented individuals who are both entrepreneurs and technology specialists. Our teams embody the spirit of innovation and entrepreneurship, enabling us to develop solutions most efficiently. Our commitment to sustainable growth is unwavering, and we continuously strive for accelerated transformation and continuous improvement. Through ALTEN labs, mentoring programs, internal universities, and more, we are always pushing boundaries and embracing new possibilities. We offer incredible opportunities to join inspiring projects in the most innovative companies. We prioritise your career development with personalised support plans tailored to your own aspirations. We're here to empower you and help you reach your full potential. Join our passionate team and start building tomorrow, today!

In Short You Get:

• A personalised career path and a rewarding management style.
• A chance to work on the most exciting engineering projects and technologies along with Premium Customers.
• A huge diversity of engineering projects and industries.
• A competitive salary.
• Private Medical Insurance.
• Pension Scheme.
• Cycle‐to‐work Scheme among many additional benefits.
• Social atmosphere, regular gatherings, and team buildings.
• Flexible way of working (role dependent).

This role will require you to have or be willing to go through Security Clearance. As part of the onboarding process candidates will be asked to complete a Baseline Personnel Security Standard; details of the evidence required to apply may be found on the government website Gov.UK. If you are unable to meet this and any associated criteria, then your employment may be delayed, or rejected. Details of this will be discussed with you at interview.