Software Integration Engineer III/IV

Zone 5 Technologies • San Luis Obispo, CA

4d • $136,000 - $210,000

About The Position

The Software Integration Engineer III–IV is a senior individual contributor responsible for owning system interfaces and integrating subsystems so they communicate reliably. The role integrates flight software, avionics, sensors, payloads, datalinks, ground systems, and vendor equipment; verifies interfaces through laboratory, ground, and flight testing; and works with GNC, avionics, software, systems, and flight test teams to support safe and reliable aircraft performance. Engineers at this level serve as the technical authority for the interfaces they own.

Level III engineers (5+ years of experience) own multiple subsystem interfaces end to end, author and maintain ICDs, negotiate interface agreements, plan integration and interface test campaigns, lead complex cross-subsystem anomaly investigations, and provide technical guidance to junior engineers. Level IV engineers (8+ years of experience) may serve as interface authority for a full platform or multiple platforms, own interface architecture and system data flow, define interface and messaging standards and compatibility strategy, lead integration of third-party, customer, and government-furnished systems, represent interfaces in design reviews and customer engagements, and resolve high-risk integration problems while mentoring engineers.

The position supports prototype and development environments and may involve integration events, flight and field testing, and mission operations as needed. The role requires a bachelor's degree in a relevant technical discipline, applicable safety-critical systems integration experience, and the ability to obtain and maintain a U.S. security clearance. The listed annual pay range is $136,000–$210,000, with separate ranges of $136,000–$182,000 for Level III and $164,000–$210,000 for Level IV.

Requirements

• Bachelor’s degree in Aerospace Engineering, Electrical Engineering, Mechanical Engineering, Systems Engineering, Computer Engineering, Computer Science, or a related technical field.
• Level III: 5+ years of relevant experience in system integration, interface development, or verification and validation of aerospace, defense, or other safety-critical systems.
• Level IV: 8+ years of relevant experience in system integration, interface development, or verification and validation of aerospace, defense, or other safety-critical systems.
• Demonstrated experience authoring and owning ICDs and interface requirements.
• Strong knowledge of communication protocols and data buses such as Ethernet (TCP/UDP), serial (RS-232/422/485), CAN, MIL-STD-1553, and ARINC 653.
• Experience integrating subsystems from multiple teams or vendors into a working system.
• Understanding of aircraft systems and avionics integration.
• Strong proficiency in one or more of C/C++, Python, and MATLAB/Simulink.
• Hands-on experience with software-in-the-loop (SITL) and/or hardware-in-the-loop (HITL) test environments.
• Experience with network and bus analysis tools such as Wireshark or CAN/1553 bus analyzers.
• Track record of planning and executing integration campaigns from requirements through final report.
• Strong analytical, problem-solving, and troubleshooting skills.
• Excellent communication and teamwork skills, including negotiating interface agreements and briefing technical results to engineering leadership and customers.
• Ability to obtain and maintain a U.S. security clearance.

Nice To Haves

• Experience with autonomous aircraft, UAVs, missiles, or robotic systems.
• Familiarity with DDS, ROS2, MAVLink, STANAG 4586, or other UAS messaging standards.
• Experience with UAI (Universal Armaments Interface) and integrating, testing, or supporting mission stores on fixed-wing jet aircraft.
• Experience with military-grade GNSS receivers and navigational systems.
• Familiarity with open architecture standards such as WOSA.
• Experience integrating datalinks, radios, and ground control systems.
• Understanding of guidance, navigation, and control architectures.
• Experience with time synchronization such as PTP, IRIG-B, or GPS time.
• Familiarity with DO-178C, DO-160, and Model-Based Systems Engineering (MBSE), including SysML interface modeling.
• Experience with flight-critical or safety-critical software.
• Familiarity with VxWorks or other RTOS environments.
• Experience with DevOps workflows and automated infrastructure.
• Experience supporting flight tests or operational deployments.
• Active U.S. security clearance.

Responsibilities

• Own system and subsystem interfaces across flight software, avionics, sensors, payloads, datalinks, and ground control systems.
• Author, maintain, and configuration-control ICDs, interface requirements, message definitions, and data dictionaries in collaboration with systems engineering.
• Coordinate interface changes with internal teams, vendors, and customers.
• Define interface architecture, including protocols, message sets, rates, timing, and error handling.
• Assess proposed interface changes and manage versioning and backward compatibility.
• Write software to integrate new components into Zone 5 systems and to integrate Zone 5 systems into existing platforms.
• Plan integration sequences and system build-up from component level through the full air vehicle.
• Develop and execute interface and system-level integration and verification tests traceable to ICDs and requirements.
• Develop simulators, emulators, and test harnesses for external systems.
• Troubleshoot complex failures using bus and network captures, telemetry, logs, and system diagnostics.
• Plan and support HITL, SITL, iron-bird, simulator, ground, and flight testing, representing the software organization to the broader test community.
• Ensure test execution complies with safety requirements and test objectives.
• Lead anomaly investigations, identify root causes, and drive corrective actions to closure.
• Coordinate software integration activities across multiple platforms.
• Collaborate with software, systems, controls, guidance, avionics, and hardware teams.
• Design and improve automated interface testing, continuous integration, and HITL/SITL infrastructure.
• Provide technical mentorship and conduct code, ICD, and test reviews for junior engineers.
• Integrate feedback from Test and Evaluation and Production into procedures and test plans.
• Represent interfaces and integration in design reviews, test readiness reviews, and customer engagements.
• Support integration events, flight testing, field testing, and mission operations as needed.
• Ensure compliance with applicable industry standards, safety requirements, and regulatory guidelines.
• Research emerging technologies and recommend improvements to integration activities.
• Operate effectively in fast-paced prototype and development environments.

Benefits

• Competitive total compensation package.
• Comprehensive benefit package options including medical, dental, vision, life, and more.
• 401(k) with company match.
• 3 weeks of paid time off each year.
• 40 hours of sick time.
• 12 annual company holidays.
• Opportunities for professional development and career advancement.

What This Job Offers

• Job Type: Full-time
• Career Level: Senior