Date Posted:2026-03-27Country:United States of AmericaLocation:US-MA-TEWKSBURY-TB1 50 Apple Hill Dr ASSABET BLDGPosition Role Type:OnsiteU.S. Citizen, U.S. Person, or Immigration Status Requirements: The ability to obtain and maintain a U.S. government issued security clearance is required.​ U.S.
JSfirm
C5I Principal Software Engineer
Job Description:

Date Posted:

2026-03-27

Country:

United States of America

Location:

US-MA-TEWKSBURY-TB1 50 Apple Hill Dr ASSABET BLDG

Position Role Type:

Onsite

U.S. Citizen, U.S. Person, or Immigration Status Requirements:

The ability to obtain and maintain a U.S. government issued security clearance is required.​ U.S. citizenship is required, as only U.S. citizens are eligible for a security clearance

Security Clearance Type:

DoD Clearance: Secret

Security Clearance Status:

Active and existing security clearance required after day 1

At RTX, the world 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 spanet 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.

We are seeking a Principal Software Engineer to support the C5I (Command, Control, Communications, Computing, Cyber and Intelligence) product line within the Missile Defense Sensors (MDS) Software Department. Our teams deliver world‑class software across an ecosystem of technologies and applications, including Linux services, microservices architectures, REST APIs, Windows front‑end applications, and HTML/TypeScript UIs.

C5I applications are implemented using a wide range of languages, including C++, Java, JavaScript/TypeScript, Lua, C, and Python, and are built and delivered through modern CI/CD pipelines. We operate within Agile and DevSecOps principles, enabling high‑frequency, high‑quality deployments across the value stream.

This position is located onsite in Tewksbury, Massachusetts.

What You Will Do

  • Lead the design, development, testing, and deployment of complex software solutions across the C5I software suite, including Linux applications, microservices, REST APIs, Windows front-end applications, and HTML/TypeScript UIs.

  • Develop and implement sophisticated algorithms to solve challenging technical problems and optimize performance and functionality in mission-critical systems.

  • Analyze, implement, and test software modifications to enhance functionality, performance, and reliability of existing system baselines.

  • Determine root cause of failures and engineer corrective solutions using advanced debugging tools.

  • Provide critical insight into system‑level design, including hardware/software trade-offs, integration of COTS solutions, software reuse opportunities, and requirements synthesis from system to component level.

  • Work closely with Systems Engineering, Integration & Test, and Platform teams to ensure seamless component integration and alignment of requirements.

  • Recommend improvements to documentation quality and refine development process standards to enhance team efficiency and alignment.

  • Provide technical guidance to the scrum team during planning and execution while mentoring junior and mid‑level engineers.

  • Work under general direction, independently developing and determining approaches to complex technical solutions.

What You Will Learn

  • How to design, develop, and integrate multi‑language, multi‑platform C5I components spanning services, UIs, and mission-critical applications.

  • Advanced techniques for developing and optimizing complex algorithms and evaluating hardware/software trade-offs.

  • Cross-functional collaboration strategies with Systems Engineering, Integration & Test, and Platform teams to ensure end‑to‑end capability delivery.

  • Agile and DevSecOps best practices supporting high-frequency, high-quality deployment pipelines.

  • Leadership and mentorship skills that foster technical growth across teams.

Qualifications You Must Have

  • Typically requires a Bachelor’s in Science, Technology, Engineering or Mathematics (STEM) and a minimum of 8 years of prior relevant experience unless prohibited by local laws/regulations.

  • Experience as a software developer in C++ and/or Java, including Git workflows, code reviews, unit testing, and development in RedHat/Linux or UNIX environments.

  • Experience developing software in an Agile Scrum or Kanban team environment.

  • Experience using debugging tools to identify and resolve software defects and optimize performance.

  • Ability to obtain U.S. government issued Secret security clearance is required after start date. U.S. citizenship is required, as only U.S. citizens are eligible for a security clearance.

Qualifications We Prefer

  • Domain knowledge in Command‑and‑Control operations including Link16, HMI usability, Mission Defense Planning, Simulation & Modeling, and Threat Evaluation/Weapon Assignment (TEWA).

  • Experience designing large‑scale modularized, reusable product bases supporting multiple derived products.

  • Proven ability to interface with customers and lead technical solutions based on complex user requirements.

  • Experience with JIRA, Confluence, Git-based workflows, CI/CD tooling, Eclipse, Ansible, Bitbucket, Artifactory.

  • Familiarity with IPDS and CMMI‑compliant gate reviews.

  • Experience applying AI tools to software engineering and familiarity with MBSE tools such as Cameo.

  • Proven experience developing software for large, complex defense systems.

  • Strong collaboration and communication skills with the ability to work under general direction while determining approaches to solutions.

What We Offer

  • Our values drive our actions, behaviors, and performance with a vision for a safer, more connected world. At RTX we value: Safety, Trust, Respect, Accountability, Collaboration, and Innovation.

  • Relocation Eligible.

Learn More & Apply Now!

Please ensure the role type defined below is appropriate for your needs before applying to this role. This position is classified as:

Onsite: Employees who are working in Onsite roles will work primarily onsite. This includes all production and maintenance employees, as they are essential to the development of our products.

This position requires a security clearance. DCSA Consolidated Adjudication Services (DCSA CAS), an agency of the Department of Defense, handles and adjudicates the security clearance process. More information about Security Clearances can be found on the US Department of State government website here: https://www.state.gov/m/ds/clearances/c10978.htm 

As part of our commitment to maintaining a secure hiring process, candidates may be asked to attend select steps of the interview process in-person at one of our office locations, regardless of whether the role is designated as on-site, hybrid or remote.

The salary range for this role is 107,500 USD - 204,500 USD. The salary range provided is a good faith estimate representative of all experience levels. RTX considers several factors when extending an offer, including but not limited to, the role, function and associated responsibilities, a candidate’s work experience, location, education/training, and key skills.

Hired applicants may be eligible for benefits, including but not limited to, medical, dental, vision, life insurance, short-term disability, long-term disability, 401(k) match, flexible spending accounts, flexible work schedules, employee assistance program, Employee Scholar Program, parental leave, paid time off, and holidays. Specific benefits are dependent upon the specific business unit as well as whether or not the position is covered by a collective-bargaining agreement.

Hired applicants may be eligible for annual short-term and/or long-term incentive compensation programs depending on the level of the position and whether or not it is covered by a collective-bargaining agreement. Payments under these annual programs are not guaranteed and are dependent upon a variety of factors including, but not limited to, individual performance, business unit performance, and/or the company’s performance.

This role is a U.S.-based role. If the successful candidate resides in a U.S. territory, the appropriate pay structure and benefits will apply.

RTX anticipates the application window closing approximately 40 days from the date the notice was posted. However, factors such as candidate flow and business necessity may require RTX to shorten or extend the application window.

RTX is an Equal Opportunity Employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, age, disability or veteran status, or any other applicable state or federal protected class. RTX provides affirmative action in employment for qualified Individuals with a Disability and Protected Veterans in compliance with Section 503 of the Rehabilitation Act and the Vietnam Era Veterans’ Readjustment Assistance Act.

Privacy Policy and Terms:

Click on this link to read the Policy and Terms

Company Details
Raytheon Technologies
870 Winter Street
Waltham, Massachusetts 02451 USA
www.rtx.com/
839 Open Jobs Available
Raytheon Technologies Corporation is an aerospace and defense company that provides advanced systems and services for commercial, military and government customers worldwide. It includes four industry-leading businesses—Collins Aerospace, Pratt & Whitney...

Supported Manufacturers:
Bombardier

Supported Models:
Challenger, Global
(Job and company information not to be copied, shared, scraped, or otherwise disseminated/distributed without explicit consent of JSfirm, LLC)
Job Info
Location
tewksbury, Massachusetts, United States
Type
Permanent
Company Details
Raytheon Technologies
870 Winter Street
Waltham, Massachusetts 02451 USA
www.rtx.com/
839 Open Jobs Available
Raytheon Technologies Corporation is an aerospace and defense company that provides advanced systems and services for commercial, military and government customers worldwide. It includes four industry-leading businesses—Collins Aerospace, Pratt & Whitney...

Supported Manufacturers:
Bombardier

Supported Models:
Challenger, Global

JSfirm, LLC

Roanoke, TX

jobs@jsfirm.com

JSfirm LLC, Privacy Policy

All rights reserved. 2001-2026 JSfirm