Senior Accountant

Hyper Light 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 Hyper Light'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 Hyper Light, 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.

• 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).

• 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.

• 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.

• 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…