Principal C/C++ Engineer

Salary: $99000 - 188000 per year Requirements: We typically require a degree in Science, Technology, Engineering, or Mathematics and at least 8 years of relevant experience, unless restricted by local laws or regulations. We need experience with C++, C, and/or Java. You must be able to obtain and maintain a U.S. government-issued Interim Secret security clearance before your start date. U.S. citizenship is required because only U.S. citizens are eligible for a security clearance. Preferred background includes knowledge of data structures and algorithms, systems software design, operating systems, architectures, and software development life cycle processes. Experience with Windows and Linux, GIT, Jira, Jenkins, Perl, Bash, and Kornshell is preferred. Experience working in a team-based development environment, ideally Agile/SCRUM or DevOps, and with test automation is preferred. Strong problem-solving and communication skills, including the ability to produce technical documentation, are preferred. Willingness to learn new technologies and tools is preferred. Ability to travel domestically and internationally is preferred. Demonstrated effectiveness in collaborating with coworkers and working across different work and conflict resolution styles is preferred. Responsibilities: We support the requirements, design, development, and testing of real-time embedded software, application software, and tools. We develop new work products and enhance existing applications and systems. We design, code, test, integrate, and document software solutions. We participate in internal reviews of software components and systems. We collaborate with project managers and other engineering professionals. We follow established development practices and processes to maintain software configuration management. We work across multiple programs and platforms within a software product line. We contribute to a range of tasks, including real-time software development, application development, test and verification, data analysis, and software tools development. Technologies: Bash DevOps Embedded Git Support JIRA Java Jenkins Linux Perl Security Windows C++ Flow More: We are RTX, the worlds largest aerospace and defense company, bringing together 185,000 people united by purpose to solve complex challenges and help create a safer, more connected world. Our Keystone AI team in Tewksbury, Massachusetts is seeking Senior Software Engineers for a 100% onsite role focused on software development across multiple languages and platforms. We offer a collaborative environment built on Safety, Trust, Respect, Accountability, Collaboration, and Innovation, along with relocation eligibility and a broad benefits package that may include medical, dental, vision, retirement savings, paid time off, leave programs, an employee assistance program, and more. The role is based in Tewksbury, Massachusetts, and candidates should expect onsite work as well as participation in a secure hiring process. last updated 27 week of 2026