Principal FSW Engineer

AST SpaceMobile is building the first and only global cellular broadband network in space to operate directly with standard, unmodified mobile devices based on our extensive IP and patent portfolio and designed for both commercial and government applications. Our engineers and space scientists are on a mission to eliminate the connectivity gaps faced by today’s five billion mobile subscribers and finally bring broadband to the billions who remain unconnected.

Position Overview

We are seeking a Principal Flight Software Engineer with deep expertise in embedded Linux and networking to join our Flight Software Team. This role is central to the design and development of our satellite fleet's Linux-based networking capabilities, with a specific focus on networking subsystems; general embedded computing knowledge is also crucial, since there are RTOS platforms in our stack that are not Linux. The ideal candidate brings hands-on embedded experience, a focus on process improvement, and the technical leadership to drive architectural decisions across the team. 

Key Responsibilities:

• Lead the design, development, and deployment of embedded Linux software for flight systems, including BSP bring-up, device driver development, and system-level integration.
• Own the networking subsystem architecture for satellite flight software, including protocol stack implementation, network driver development, and link-layer communication.
• Collaborate with hardware, RF, and systems engineering teams to define interfaces and integrate networking subsystems with spacecraft hardware.
• Define and enforce software architecture, coding, and review standards across the Flight Software Team.
• Mentor junior and mid-level engineers; conduct code reviews and contribute to engineering best practices.
• Support Software-in-the-Loop (SiL) simulation environments that accurately reflect flight networking behavior.
• Participate in integration and test activities, diagnosing and resolving complex hardware/software issues.
• Lead technical projects end to end - scoping, planning, staffing, and driving them to delivery.
• Own the larger systems and processes the team depends on: build and CI infrastructure, release and configuration management, and software development lifecycle standards.
• Serve as the Flight Software technical point of contact for other engineering teams and program leadership, communicating status, risk, and trade-offs. 

Qualifications 

Education:

Experience:

• 8+ years of professional software engineering experience, with significant focus on embedded Linux.
• Deep expertise in Linux kernel internals: network and platform driver development, device tree authoring, and kernel configuration and build.
• Strong understanding of networking fundamentals: TCP/IP, UDP, routing, network interfaces, and socket programming.
• Experience implementing or integrating custom communication protocols at the application, transport, or link layer.
• Proficiency in C and C++ (C++17 standard library); Python for tooling and automation.
• Experience with embedded Linux build systems such as Yocto or Buildroot.
• Familiarity with cross-compilation toolchains and embedded debugging techniques (JTAG, SWD, GDB).
• Experience with real-time or latency-constrained Linux environments (PREEMPT_RT or similar).
• Strong debugging skills across hardware/software boundaries; comfortable with oscilloscopes, logic analyzers, and network analyzers.
• Practicing modern development workflows: Git, unit testing, continuous integration, Jira.
• Track record leading projects that extend beyond a single embedded target - larger systems, services, or engineering infrastructure and tooling.
• Experience defining and improving engineering processes that span multiple teams. 

Preferred Qualifications:

• Background in RF or radio-frequency systems integration.
• Experience with network security in embedded contexts (TLS, secure boot, key management).
• Experience with CUDA.
• Experience with high-reliability or fault-tolerant software design patterns. 

Soft Skills:

• Excellent written and verbal communication skills.
• Able to lead technical discussions across engineering and program teams.
• Skilled at extracting requirements from stakeholders. 

Technology Stack:

• Embedded Linux kernel development, device drivers, and device tree authoring.
• C, C++ (C++17), and Python for tooling and automation.
• Embedded Linux build systems such as Yocto and Buildroot.
• Cross-compilation toolchains and embedded debugging tools (JTAG, SWD, GDB).
• Real-time Linux environments (PREEMPT_RT or similar) and RTOS platforms.
• Git, unit testing frameworks, CI pipelines, and Jira.
• Hardware/software debugging equipment, including oscilloscopes, logic analyzers, and network analyzers. 

Physical Requirements  

• Ability to lift up to 25 lbs.
• Ability to use a computer for extended periods.
• Ability to work in an office and lab environment, including hands-on hardware/software debugging using oscilloscopes, logic analyzers, and network analyzers.
• Ability to travel occasionally to support integration, testing, or cross-team collaboration as needed.

This job description may not be inclusive to the duties and responsibilities listed. Additional tasks may be assigned to the employee from time to time or the scope of the job may change as needed by business demands. 

AST SpaceMobile is an Equal Opportunity, at will Employer; employment is governed on the basis of merit, competence and qualifications and will not be influenced in any manner by race, color, religion, gender, national origin/ethnicity, veteran status, disability status, age, sexual orientation, gender identity, marital status, mental or physical disability or any other legally protected status.