Senior Software Engineer ATMS

RTX (Raytheon); Harlow; Hybrid; GBP 70,000 - 95,000; Full time

Benefits offered by this job

Competitive salary

Pension scheme (up to 10.5% company)

Life Assurance 6x salary

25 days holiday + buy/sell up to 5

Company bonus scheme 4%

Flexible Benefits (Health Cashplan, OH

Enhanced sick pay

Enhanced family friendly policies

Job summary

RTX (Raytheon) is seeking a Senior Software Engineer for the ATMS Team in Harlow, UK. You will design, develop, and test real-time embedded software to support global customers, while collaborating with cross-functional teams and internal R&D projects.

The role requires hands-on embedded software development, proficiency in C/C++/C#, UML, RTOS, and low-level communications. You will participate in design reviews and contribute to continuous improvement within an Agile/DevOps environment.

Qualifications

• Must have hands-on software development experience in a team environment.
• Experience with C/C++/C# in real-time embedded systems.
• UML usage in software design required.
• Strong RTOS and embedded software programming background.

Responsibilities

• Design and develop real-time embedded software for ATMS systems.
• Lead design reviews and contribute as a Subject Matter Expert.
• Investigate and resolve software defects across the lifecycle.
• Create test plans to ensure Raytheon quality standards.
• Interface with vendors and internal teams to support programs.

Skills

C/C++/C#

UML

RTOS

Real-Time Embedded

Ethernet

Fault investigation

Version control

Education

2:1 degree in CS

Tools

Git

JIRA

CI/CD

Job description

Date Posted: 2026-09-16

Country: United Kingdom

Location: Harlow, Essex

Position Role Type: Hybrid

Benefits

• £: Competitive salary
• Contributory Pension Scheme (up to 10.5% company contribution)
• 6 times salary 'Life Assurance' with pension
• 25 days holiday (increasing with service) + statutory public holidays, plus opportunity to buy and sell up to 5 days (37hr)
• Company bonus scheme 4% (discretionary)
• Flexible Benefits scheme with extensive salary sacrifice schemes, including Health Cashplan, Dental, and Cycle to Work amongst others
• Enhanced sick pay
• Enhanced family friendly policies including enhanced maternity, paternity & shared parental leave

Work Culture

37hr working week, although hours may vary depending on role, job requirement or site-specific arrangements.

Early 1.30pm finish Friday, start your weekend early!

Remote, hybrid and site based working opportunities, dependant on your needs and the requirements of the role.

Up to 5 paid days volunteering each year.

Flexible working culture focused on output, with more formal flexible working arrangements on request (assessed subject to role) - please highlight any requests to the Talent Acquisition team.

Position Details

Function: Engineering

Location: Harlow (Hybrid with 4 days a week on site)

Clearance: SC Eligible

Hours: 37 hours per week with early finish on Fridays

Company Overview

At RTX, the world's largest aerospace and defense company, 185,000 great minds are united by purpose and inspired to make a difference solving the world's most complex problems. With our three market leading businesses, world-class operations and investments in research and development, we offer capabilities and opportunity no one else can. Together, we push the boundaries of known science and find new ways to connect and protect our world. Raytheon brings the strength of more than 100 years of experience and renowned engineering expertise to meet the needs of today's mission and stay ahead of tomorrow's threat. We deliver solutions that help our nation and allies defend freedoms and deter aggression, creating a safer, more secure world. Join us and help shape the future of aerospace and defense.

Summary of Role

Raytheon's ATMS (Air Traffic Management Systems) Software team is seeking talented, enthusiastic and innovative individuals that thrive within an Agile eco-system to deliver world class solutions that make the world a safer place. Become a part of something greater than yourself by bringing your best in collaboration with other motivated and talented individuals across a diverse set of backgrounds and skill sets.

Main Duties

Main Duties:

• As a Senior Software Engineer you will work within our existing software engineering team bringing your experience of real-time embedded software engineering to design, develop, integrate and test systems software to support our worldwide customer base. You will also have opportunity to work on exciting internal R&D projects to support the next generation of ATMS systems.
• Design and develop product functionality, user interfaces and performance improvements.
• Key contributor & reviewer at gate & design reviews.
• Act as Subject Matter Expert as part of a wider software and systems engineering group to analyse and resolve software and system defects in response to service requests, incidents, problems and events.
• Validating and verifying the design artefacts from internal teams or subcontractors.
• Provide input to configuration, safety and quality management as appropriate.
• Document design and advise on product support material.
• Investigate product issues and develop solutions to customer problems.
• Develop test plans and methodologies to ensure product meets Raytheon quality standards.
• Lead continuous technical improvement and re-architecting activities.
• Assist in updating software design artefacts.
• Interfacing with COTS vendors for technical support.
• Provide technical support (covering the entire software lifecycle) to Raytheon programmes delivering new capability.

Candidate Requirements

Essential

• Relevant years' active, hands-on software development experience, working in a Team environment
• Relevant years' experience with C/C++/C# language
• Experience in the use of UML in software design and other methodologies
• Real-Time Embedded SW programming experience
• RTOS knowledge
• Knowledge of low-level communication protocols, Ethernet, Serial, PCI Bridge
• Hands on fault investigation experience in embedded code environment
• Use of tools in software configuration management, requirements definition, high-level and detailed design, defect reporting

Desirable

• Min 2:1 degree in a computer science or related subject
• Experience Working in an Agile/SCRUM/DevOps delivery model.
• Knowledge of Radar systems.
• Hands-on experience in reverse engineering a mature system to take advantage of a modern technology development in hardware, software and firmware.
• Competency with design patterns and their application to solve complex problems.
• #LI-MF1

Additional Information

RTX adheres