Test Engineer III

Job Summary

At Mercury Systems, your work has real-world impact. As part of a team building trusted, secure, and high-performance technology for aerospace and defense missions, you'll help solve some of the toughest engineering challenges in the industry. Our servers and secure processing solutions power critical missions—from protecting national security to enabling next-generation aerospace systems.

As a Test Engineer III, you'll be at the center of this mission: validating ruggedized systems that must perform flawlessly in extreme environments, ensuring reliability where it matters most. If you're excited by complex engineering problems, advanced technology, and work that directly supports those who protect our nation, this role offers the opportunity to make a meaningful difference every day.

The Test Engineer III will lead test efforts in developing and executing server systems for mission critical aerospace and defense applications. This role plays a pivotal part in ensuring product reliability, performance, and security across the full engineering lifecycle from concept to sustainment.

• Implement standardized system testing practices across Mercury's ruggedized servers and secure software product lines.
• Design and implement robust test procedures that meet military standards (e.g., MIL-STD-810, DO-461, DO-167, DO-178C, DO-254) and cybersecurity requirements
• Oversee and conduct functional, environmental, stress, and security testing of hardware and software systems, ensuring performance in extreme conditions and mission‑critical environments
• Collaborate with software development teams to integrate and validate secure software solutions
• Partner with systems engineering, hardware design, and software development teams to align test objectives with product requirements; coordinate with program managers to meet timelines and deliverables
• Ensure all testing procedures developed comply with strict security protocols and regulatory standards, leveraging active security clearance for classified projects
• Support the development of tools to streamline test analysis, reporting, and documentation
• Assist in defining and developing tools to streamline test analysis and reporting
• Establish and maintain test requirements for test equipment and working with Test Support to bring test equipment to operational status
• Prepare comprehensive test documentation including acceptance test plans, test reports, and performance metrics for internal stakeholders and external customers, including government agencies as well as present findings to senior leadership and clients
• Support the standardization of systems used to track testing issues and document results
• Collaborate with Mission Assurance teams to conduct root cause analyses for issues identified during testing and sustainment

• Bachelor of Science degree in Engineering or a related field. Equivalent experience of will be considered which t typically requires a minimum of 5 years of experience in test ing similar systems
• Prior experience with Aerospace, Defense, Government, or Military sectors
• Proven ability to develop performance metrics and lead initiatives to achieve engineering and operational goals
• Broad testing expertise across hardware, electrical, and software systems
• Solid understanding of system and subsystem requirements & specification generation processes
• Experience in developing and executing verification and validation test procedures
• Hands‑on experience testing ruggedized servers for harsh environments (e.g., extreme temperatures, shock, vibration)
• Proficiency in secure software testing, including vulnerability assessments, penetration testing, and cryptographic module validation
• Familiarity with military standards such as MIL-STD-810, MIL-STD-461, and MIL-STD-1275
• General understanding of engineering principles and demonstrated application of those concepts with a focus on safety and regulatory compliance
• Ability to obtain and maintain an active U.S. Secret Security Clearance

This position requires you to have or can obtain a government security clearance. Security clearances may only be granted to U.S. citizens.