Senior Accountant

HyperLight is at the forefront of the commercialization of thin-film lithium niobate (TFLN) integrated photonics — a material and process technology that is enabling high-performance, scalable optical components across AI/datacom infrastructure, hyperscale computing, quantum computing, sensing, and beyond. Founded in 2018 and backed by leading venture capital, we’ve built a team and a platform focused on real-world mass deployment of TFLN photonics technology. At the core of our work is the TFLN Chiplet™ platform — a modular, integrated architecture designed for scalability, manufacturability, and seamless integration into complex systems. It offers a rare combination of extraordinary performance and industrial readiness, enabling system developers across applications to deploy the technology fast and ready. We partner with our customers and suppliers from conceptualization, design, and prototyping phases, all the way through mass production to ensure smooth and rapid deployment of TFLN photonic technology. We believe our platform is the key, in the golden age of integrated photonics, to empower humanity to the next level. We assembled a world class team covering engineering, business, and operations. We believe in the power of integrity, innovation, collaboration, and pragmatic solutions. Our diverse team thrives on challenges and is united by a shared commitment to excellence. We take pride in tackling complex challenges with curiosity, humility, and a deep sense of care for one another. We are seeking a detail-oriented, hands-on Senior Accountant to join HyperLight's finance team at our Cambridge, MA headquarters, reporting directly to the Corporate Controller. This role owns the day-to-day operational accounting that keeps the business running: accounts payable, accounts receivable, customer billing, and fixed asset accounting — with active participation in the monthly close. At HyperLight, you'll join a world-class team working at the frontier of integrated photonics – combining materials science, system design, and scalable manufacturing. As we scale, the operational accounting foundation you build and maintain will be critical to keeping vendors paid, customers invoiced accurately, and our asset base properly tracked across labs, production, and corporate environments. RESPONSIBILITIES Accounts Payable Own the full AP cycle: vendor invoice intake, coding, approval routing, three-way matching against POs and receipts, and timely payment runs. Maintain accurate vendor master data, including W-9s, banking details, and payment terms; lead 1099 reporting at year-end. Partner with operations, lab, and engineering teams to resolve invoice and PO discrepancies quickly. Drive process improvements and automation across the AP function (e.g., AP automation tools, expense management integration). Accounts Receivable and Billing Own the customer billing process: generate invoices in line with contracts, milestones, and shipment activity; ensure accuracy and timeliness. Manage AR aging and collections; partner with sales and legal on collections escalations and dispute resolution. Apply cash receipts accurately and reconcile customer accounts. Maintain customer master data and support new customer onboarding from a finance/credit perspective. Fixed Assets Own the fixed asset sub-ledger: capitalize new assets, maintain accurate descriptions, locations, useful lives, and depreciation schedules. Partner with lab, manufacturing, and IT teams on physical asset tracking, including periodic asset verifications and disposal documentation. Track CIP (construction-in-progress) for lab build-outs and manufacturing equipment; transfer to fixed assets upon placement in service. Ensure proper accounting treatment of capital vs. expense items in line with company policy and US GAAP. Month-End Close and General Accounting Prepare and post journal entries related to AP, AR, fixed assets, prepaids, and accruals as part of the monthly close. Reconcile assigned balance sheet accounts; investigate and resolve reconciling items. Support external audit and tax requests, including PBC schedules, supporting documentation, and audit walk-throughs. Help maintain accounting policies, SOPs, and internal controls; identify and implement process improvements. Bachelor's degree in Accounting, Finance, or a related discipline. 4+ years of progressive accounting experience, ideally including time in industry (high-growth, hardware, or manufacturing preferred). Strong working knowledge of US GAAP and standard accounting processes across AP, AR, billing, and fixed assets. Hands-on experience with a major ERP (NetSuite preferred); comfort configuring AP/AR workflows, sub-ledgers, and reports. Experience with AP automation, expense management, and billing tools (Ramp preferred). Strong Excel skills (pivot tables, lookups, reconciliation workflows). High attention to detail, strong organizational skills, and the ability to manage multiple priorities against month-end deadlines. Excellent communication and collaboration skills; comfort partnering with non-finance stakeholders to resolve issues at the source. High ownership mindset and comfort operating in a fast-moving startup environment where processes are still being built. CPA license and Big 4 (or national firm) audit experience strongly preferred. Competitive market-based compensation (Salary range of $85,000 - $150,000 per year) Comprehensive health coverage, including medical, vision, and dental plans for individuals and families 401(k) retirement plans with employee matching Paid Parental Leave Life and disability insurance Commuter benefits and subsidies Professional growth and mentorship opportunities HyperLight is an equal opportunity employer. All applicants will be considered for employment without attention to race, color, religion, sex, sexual orientation, gender identity, national origin, veteran or disability status. HyperLight is committed to providing reasonable accommodations to individuals with disabilities during our hiring process. If you need assistance or an accommodation, please contact us at View email address on click.appcast.io. #J-18808-Ljbffr