James Zammit

James Zammit
Occupation	Entrepreneur, software engineer
Known for	Co-founder and CEO of Roark

James Zammit is a Maltese software engineer and entrepreneur. He is the co-founder and chief executive officer of Roark, a company that provides testing, monitoring, and evaluation tools for voice AI agents. Roark was part of Y Combinator's Winter 2025 batch.

Career

Zammit has over ten years of experience as an infrastructure and AI engineer. He previously worked at AngelList, where he contributed to core infrastructure as the company scaled from $10 billion to $124 billion in assets under management. At AngelList, he led the development of Relay, an AI-powered portfolio manager that processed thousands of financial documents monthly.

Prior to AngelList, Zammit co-founded multiple startups. He was co-founder and chief technology officer of Infobot and Kwaver, where he built real-time collaboration and customer-facing chat platforms. One of his earlier startups partnered with Firebase and was showcased at Google I/O in 2016. Zammit has been awarded scholarships from both Meta and Apple.

Zammit co-founded Roark alongside Daniel Gauci Mizzi, who serves as chief technology officer. The company is based in San Francisco and operates in the conversational AI and analytics sectors. Roark's platform is designed to address reliability challenges in voice AI by providing a quality assurance layer for voice agents. The platform offers over 40 built-in metrics — including latency tracking, instruction-following analysis, repetition detection, and sentiment analysis — along with custom dashboards and alerting capabilities. It supports multi-speaker analysis for calls with up to 15 participants, with automatic speaker identification.

A key feature of Roark's product is its simulation and persona testing system, which enables end-to-end phone and WebSocket simulations for both inbound and outbound voice agents. Users can configure personas with different accents, languages, and behavioral profiles, and define test scenarios using a graph-based approach to cover edge cases. The platform also implements a feedback loop in which failed calls are automatically converted into repeatable tests.

As of early 2025, Roark had processed over 10 million minutes of calls. The company's clients include teams across the voice AI ecosystem, and its investors include Y Combinator and AngelList.

In January 2025, Zammit announced Roark's acceptance into Y Combinator's Winter 2025 batch.