L3Harris is dedicated to recruiting and developing high-performing talent who are passionate about what they do. Our employees are unified in a shared dedication to our customers’ mission and quest for professional growth. L3Harris provides an inclusive, engaging environment designed to empower employees and promote work-life success. Fundamental to our culture is an unwavering focus on values, dedication to our communities, and commitment to excellence in everything we do.

L3Harris is the Trusted Disruptor in defense tech. With customers’ mission-critical needs always in mind, our employees deliver end-to-end technology solutions connecting the space, air, land, sea and cyber domains in the interest of national security.

Job Title - Senior Software Engineer (Autonomy & Maritime Systems)

Job Location - Portchester, UK

Job ID - 44405

About this opportunity and L3Harris UK

Operating at 10 sites in the United Kingdom, L3Harris supports Britain’s mission to secure and strengthen the country by delivering sovereign innovation across the space, air, land, sea and cyber domains.

L3Harris in Portchester is part of our Maritime UK business - a leading global supplier of integrated marine control systems and simulation products for warships, submarines and high-end commercial marine vessels worldwide. Our Maritime UK business has 4 UK locations and together we are powering the Royal Navy’s adoption of autonomous surface vehicle technology as well as delivering autonomous capability to UK ports, harbours and offshore energy service providers.

Join our Maritime Global Systems team and play a key role in delivering next-generation digital maritime solutions across vessels and offshore assets worldwide. We are seeking a highly skilled Senior Software Engineer with proven expertise in C++ software development, software architecture, and maritime autonomy systems. The successful candidate will provide technical leadership for the design, development, integration, and support of advanced autonomous and embedded software solutions across multiple strategic maritime programmes.

A few of our employee benefits are:

• Hybrid working where possible, three days onsite per week
• Flexible or part-time working arrangements considered upon request
• Half day finish on a Friday
• 25 days holiday per year (plus bank holidays), increasing with long service and with the opportunity to buy/sell up to 5 days
• Private medical insurance with optional family cover
• Pension scheme of up to 8% employer contribution
• Life Assurance 4x salary (flexible up to 10x)
• Group income protection
• Flexible opt-in extras such as a health care cash plan, dental insurance, gym membership, critical illness cover, cycle to work scheme, travel insurance and electric car scheme
• Employee Family Assistance Program providing mental health and wellbeing support
• Professional membership reimbursement (discretionary) *

What the role will involve

The responsibilities of your role will include the following:

• Lead the design, development, and architecture of high-performance C++ applications for autonomous maritime systems.
• Provide technical leadership and mentorship to software engineers, promoting best practices in software design, code quality, and system integration.
• Collaborate with systems engineering, UX, QA, product management, and external partners to deliver high-quality software solutions.
• Drive Agile software development activities, including sprint planning, reviews, retrospectives, and continuous improvement initiatives.
• Utilise JIRA, GitLab, and CI/CD pipelines to manage development activities and ensure reliable software delivery.
• Oversee and contribute to Qt-based UI development for mission-critical operator interfaces.
• Ensure software solutions are robust, scalable, secure, maintainable, and supportable throughout the product lifecycle.
• Support development, integration, deployment, and DevOps activities within Linux (RHEL 8) environments.

What you’ll bring

The role requires the following experience and skills:

• Bachelor’s degree in Computer science, Software Engineering, or equivalent practical experience.
• Minimum 5 years of professional experience in C++ software development, including embedded or real-time systems.
• Proven experience providing technical leadership within Agile and DevSecOps environments.
• Demonstrated ability to design and deliver complex, high-reliability software systems.
• Strong Linux and Git-based development experience.
• Experience with modern software development workflows and CI/CD practices.
• Strong communication, collaboration, and stakeholder engagement skills.

Preferred Additional Skills:

• Experience with the Qt framework for GUI development.
• Knowledge of DevOps tools, build automation, and CI/CD pipelines.
• Experience with autonomous systems and maritime software applications.
• Understanding of UX principles and user-centred design.
• Experience supporting IRAD, R&D, or innovation-focused development programmes.
• Familiarity with embedded systems, sensor integration, and mission management software.

Important to know

Applicants who accept a conditional offer of employment must meet the requirement of right to work in the UK and must meet eligibility requirements for access to classified information and will be subject to government security checks.

LI-Hybrid

LI-RT1

SeniorSpecialistSoftwareEngineer

L3Harris Technologies is proud to be an Equal Opportunity Employer. We are committed to maintaining a workplace that is free from unlawful discrimination and offers equal opportunities for all. Applications from individuals are encouraged regardless of age, disability, sex, gender reassignment, sexual orientation, pregnancy and maternity, race, religion or belief, and marriage and civil partnerships.

• Bachelor’s degree in Computer science, Software Engineering, or equivalent practical experience.
• Minimum 5 years of professional experience in C++ software development, including embedded or real-time systems.
• Proven experience providing technical leadership within Agile and DevSecOps environments.
• Demonstrated ability to design and deliver complex, high-reliability software systems.
• Strong Linux and Git-based development experience.
• Experience with modern software development workflows and CI/CD practices.
• Strong communication, collaboration, and stakeholder engagement skills.

Preferred Additional Skills:

• Experience with the Qt framework for GUI development.
• Knowledge of DevOps tools, build automation, and CI/CD pipelines.
• Experience with autonomous systems and maritime software applications.
• Understanding of UX principles and user-centred design.
• Experience supporting IRAD, R&D, or innovation-focused development programmes.
• Familiarity with embedded systems, sensor integration, and mission management software.

Important to know

Applicants who accept a conditional offer of employment must meet the requirement of right to work in the UK and must meet eligibility requirements for access to classified information and will be subject to government security checks.

• Flexible or part-time working arrangements considered upon request
• Half day finish on a Friday
• 25 days holiday per year (plus bank holidays), increasing with long service and with the opportunity to buy/sell up to 5 days
• Private medical insurance with optional family cover
• Pension scheme of up to 8% employer contribution
• Life Assurance 4x salary (flexible up to 10x)
• Group income protection
• Flexible opt-in extras such as a health care cash plan, dental insurance, gym membership, critical illness cover, cycle to work scheme, travel insurance and electric car scheme
• Employee Family Assistance Program providing mental health and wellbeing support
• Professional membership reimbursement (discretionary) *

L3Harris is dedicated to recruiting and developing high-performing talent who are passionate about what they do. Our employees are unified in a shared dedication to our customers’ mission and quest for professional growth. L3Harris provides an inclusive, engaging environment designed to empower employees and promote work-life success. Fundamental to our culture is an unwavering focus on values, dedication to our communities, and commitment to excellence in everything we do.

L3Harris is the Trusted Disruptor in defense tech. With customers’ mission-critical needs always in mind, our employees deliver end-to-end technology solutions connecting the space, air, land, sea and cyber domains in the interest of national security., Operating at 10 sites in the United Kingdom, L3Harris supports Britain’s mission to secure and strengthen the country by delivering sovereign innovation across the space, air, land, sea and cyber domains.

L3Harris in Portchester is part of our Maritime UK business - a leading global supplier of integrated marine control systems and simulation products for warships, submarines and high-end commercial marine vessels worldwide. Our Maritime UK business has 4 UK locations and together we are powering the Royal Navy’s adoption of autonomous surface vehicle technology as well as delivering autonomous capability to UK ports, harbours and offshore energy service providers.

Join our Maritime Global Systems team and play a key role in delivering next-generation digital maritime solutions across vessels and offshore assets worldwide. We are seeking a highly skilled Senior Software Engineer with proven expertise in C++ software development, software architecture, and maritime autonomy systems. The successful candidate will provide technical leadership for the design, development, integration, and support of advanced autonomous and embedded software solutions across multiple strategic maritime programmes.