Senior Software Engineer (5G)

About the role

We are located in San Diego, CA and we are a publicly traded communications company that has proudly been in business for over 20 years! We are on a mission to provide the highest quality service possible and bridging the digital divide across the globe. We work across a variety of different industries and we are one of the global leaders in our space that is constantly innovating and working with the latest technologies.

We are seeking a Senior Software Engineer (5G) to design, develop and optimize software for 5G modems and related subsystems. The role focuses on C++ implementation of protocol stack components and modem features, building robust abstractions (HAL/APIs), and ensuring performance and standards compliance (3GPP/GSMA). You will collaborate with RF, firmware, and systems teams to deliver 5G device and network solutions, drive technical decisions, and mentor junior engineers.

Responsibilities

• Design, implement and maintain C++ software for 5G modem components and protocol stack elements (NAS, SDAP, RRC, PDCP, RLC, MAC, PHY).
• Develop and maintain software abstraction layers (HAL) and clear, stable APIs for modem and device integration.
• Optimize performance and resource usage for real-time and embedded targets, including profiling, memory and CPU optimization.
• Integrate and test modem software with SDKs, hardware platforms and target devices; perform bring-up and debugging on lab hardware.
• Work closely with cross-functional teams (RF, firmware, system integration, QA) to define interfaces and ensure end-to-end functionality.
• Drive compliance with 3GPP and GSMA standards, interpret specifications and translate requirements into engineering tasks.
• Participate in design reviews, code reviews, and set best practices for maintainable, testable code.
• Troubleshoot complex issues across software and hardware boundaries using logs, tracing, and diagnostics tools.
• Mentor and guide junior engineers, contribute to technical planning, and influence product and architecture decisions.
• Support feature delivery for both device (5G modem, 5G devices) and network-side components (RAN, gNodeB / base station) as required.

Qualifications

• Bachelors or Masters degree in Computer Science, Electrical Engineering or related field.
• 5+ years of professional software engineering experience, with demonstrable experience in C++ development.
• Direct experience with 5G modem software and protocol stacks (required).
• Strong understanding of cellular technologies (5G and LTE) and 3GPP specifications; familiarity with GSMA guidelines.
• Proven experience with modem-related layers: NAS, SDAP, RRC, PDCP, RLC, MAC and PHY.
• Experience with embedded