Lightmatter is leading the revolution in AI data center infrastructure, enabling the next giant leaps in human progress. The company invented the world’s first 3D-stacked photonics engine, Passage™, capable of connecting thousands to millions of processors at the speed of light in extreme-scale data centers for the most advanced AI and HPC workloads. Lightmatter raised $400 million in its Series D round, reaching a valuation of $4.4 billion. We will continue to accelerate the development of data center photonics and grow every department at Lightmatter! If you're passionate about tackling complex challenges, making an impact, and being an expert in your craft, join our team of brilliant scientists, engineers, and accomplished industry leaders. Lightmatter is (re)inventing the future of computing with light! About this Role You will be focused on validating and architecting package and system-level test strategies for high-speed I/O interfaces on Lightmatter’s novel product line. In this role, you will be responsible for setting up and executing high-speed electrical characterization, driving link bring-ups, and stress-testing I/Os in system environments. You will work closely with cross-functional teams to transition these technologies into high-volume manufacturing. We are looking for an engineer with a proven track record of testing real-world industry products. You will be part of a growing interdisciplinary team with a lot of opportunities to learn and make a big impact. Responsibilities • Execute high-speed serial I/O characterization and validation across multiple platforms for Lightmatter products. • Work directly with architecture, signal integrity, and silicon design teams to understand the technology and conceptualize characterization and test techniques targeting product manufacturing. • Architect test concepts, test platforms, and design-for-test rules, providing critical feedback during the technology concept phase. • Set up and operate a wide range of high-speed lab equipment, including oscilloscopes, BERTs, AWGs, TDRs, and VNAs/PNAs. • Develop Python-based test software and scripts to automate lab measurements, test execution, data analysis, and parameter extraction. • Define and develop stress testing methodologies to identify design operating limits of serial I/Os post-system integration. • Troubleshoot and triage complex issues with compliance test hardware, fixtures, software, and the Device Under Test (DUT). • Work with vendors to specify and procure state-of-the-art test equipment. Requirements • Master’s in Electrical Engineering, Computer Engineering, or a related field. • 6+ years of industry experience in transceiver, SerDes, or high-speed link test development on products  • Extensive hands-on lab experience and familiarity with high-speed equipment, including oscilloscopes, BERTs, PPGs, VNAs, and spectrum analyzers. • Strong familiarity with high-speed interfaces and analog building blocks (e.g., PLL, CDR, CTLE, DFE, FFE, and FEC). • Experience in test system automation and data processing using Python. • Strong analytical and debugging skills to identify and solve hardware and signal integrity issues during the testing process. • Ability to convey complex technical concepts to both technical and non-technical stakeholders. Preferred Qualifications  • Hands-on experience in the characterization and testing of silicon photonics components and circuits (e.g., tunable lasers, power meters, polarization synthesizers, OBR/OVA). • Understanding of Silicon Photonics components and optical testing methodologies. • Deep knowledge of system-level SerDes design and channel analysis, including understanding insertion loss, return loss, crosstalk, and link training algorithms. • Knowledge of industry specifications such as IEEE 802.3, OIF, PCIe, or USB4. • Ph.D. with 2+ years of relevant industry experience. We offer competitive compensation. The base salary range for this role determined based on location, experience, educational background, and market data. Salary Range: total compensation goes beyond base salary, it also includes a new hire equity grant, annual performance-based equity, and other rewards that recognize your impact and contribution. $187,000—$220,000 USD Benefits • Comprehensive Health Care Plan (Medical, Dental & Vision) • Retirement Savings Matching Program • Life Insurance (Basic, Voluntary & AD&D) • Generous Time Off (Vacation, Sick & Public Holidays) • Paid Family Leave • Short Term & Long Term Disability • Training & Development • Commuter Benefits • Flexible, hybrid workplace model • Equity grants (applicable to full-time employees) Benefits eligibility may vary depending on your employment status and location. Lightmatter recruits, employs, trains, compensates, and promotes regardless of race, religion, color, national origin, sex, disability, age, veteran status, and other protected status as required by applicable law. Export Control Candidates should have capacity to comply with the federally mandated requirements of U.S. export control laws.