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Principal Software Engineer - 15% Sign on Bonus

Tewkesbury, United Kingdom; Fleet, United Kingdom

Job ID SAS20231608-104819
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Our team in the UK has an unwavering focus on our commitment to excellence in everything we do, delivering mission solutions with speed, innovation and flawless execution.

  • Full Time
  • Level: Experienced
  • Location: On Site
  • Glassdoor Reviews and Company Rating

Success Profile

What makes a successful team member at L3Harris?
Check out the traits we’re looking for and see if you have the right mix.

  • Collaborative
  • Detail-Oriented
  • Influential
  • Organised
  • Strategic
  • Technical


A dynamic market environment combined with pioneering technology and a collaborative team, makes every day interesting and engaging.

Thomas, Program Finance Manager, Crawley, UK

L3Harris Work Perks

  • Health

    • Private medical insurance and group life assurance
    • Benefit allowance to help you pay for insurance
    • Options for dental and critical illness coverage as well as a health cash plan and gym membership

  • Family

    • Employee and Family discount programme
    • Employee Assistance Programme
    • Optional partner life assurance

  • Well-Being

    • Generous annual holiday allowance
    • Retirement savings plan with employer contribution
    • Employee assistance programme to provide advice and guidance on finance, mental health, and more
    • Casual “dress for your day” policy

Job Description

L3Harris is dedicated to recruiting and developing diverse, 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 Technologies is an agile global aerospace and defense technology innovator, delivering end-to-end solutions that meet customers’ mission-critical needs. The company provides advanced defense and commercial technologies across space, air, land, sea and cyber domains. L3Harris has approximately $18 billion in annual revenue and 50,000 employees, with customers in more than 100 countries.


Job Title – Principal Software Engineer (15% Sign on Bonus)

Job Location – Tewkesbury or Fleet, UK

Flexible, condensed or reduced working hours available, i.e. 4-day condensed working week, 9-day fortnights, 12pm finish every Friday, etc.

Job ID – SAS20231608-104819

About this opportunity and L3Harris UK

From 12 UK sites, our team of over 1,400 people deliver unique capabilities across air, land, sea, space and cyber for military, security and commercial customers, worldwide.

At L3Harris, in our Intelligence & Cyber (ICI) division, we are looking for a Principal Software Engineer to support our product portfolios of Cyber Security, Integrated Air & Missile Defence and Electronic Warfare. You will have the opportunity to work across the product portfolios on a range of projects, products and software technologies.

A few of our employee benefits are:

  • 15% sign on bonus
  • £3,000 to £6,000 DV Bonus – please note this level of clearance isn’t essential for this role. This bonus is subject to individual clearance and project requirements – discussed upon application.
  • Flexible, condensed or reduced working hours available, i.e. 4-day condensed working week, 9-day fortnights,12pm finish every Friday, etc.
  • 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 7% 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 and cycle to work scheme
  • Employee assistance program providing mental health and wellbeing support
  • Professional registration with the IET

What the role will involve

The responsibilities of your role will include the following:

  • Taking a leading role in the development of complex systems and acting as the Software Technical Authority
  • Set clear standards and procedures for the software aspects of project development and delivery, tracking project progress and generating reports to stakeholders
  • Supporting the Software Engineering Team Leads, by contributing to the development of the Software Engineering Function through the promotion of best practice, tools, processes and mentoring.
  • Contribute to the generation of technical proposals, bids and presentations
  • Ensure that the team has appropriate technical competencies, skills and behaviors and developing the team to support future growth and technology/product roadmaps
  • Opportunities to participate in trials, customer demonstrations, attend conferences and perform onsite testing in a range of countries worldwide

What you’ll bring

The role of Principal Software Engineer requires the following experience and skills:

  • Solid experience of object orientated design and implementation principles
  • Previous Software Engineering experience in one or more language (C#, C++, Python, Rust, Java, etc.) with up-to-date skills and a keen interest in industry best practice
  • Track record of producing reliable, robust, intuitive, maintainable software
  • Experience of leading software engineering development projects through the software lifecycle
  • A Degree (or equivalent experience) in Computer Science/Software Engineering

Important to know

Due to the nature of our work many our roles require a UK nationality and the ability to obtain a security clearance. Applicants who accept a conditional offer of employment must meet eligibility requirements for access to classified information and will be subject to government security checks.

L3Harris Technologies is proud to be an Affirmative Action/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.





Thank you for your patience as we transition to a new applicant tracking system. Please be aware that you may have applications in more than one system at this time and, as a result, you may receive communications regarding your applications from multiple systems.

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