Photon has raised $4.5 million in a Seed funding round co-led by Gradient and A*, with participation from Vercel, HongShan, Z Fellows, Llama Ventures, Karman and other angel investors. Gradient announced the investment on October 1, 2026, and confirmed the size of the round and its co-lead role alongside A*.
Founded by Daniel Tian and Ryan Zhu, Photon develops infrastructure that allows AI agents to operate through messaging channels rather than requiring users to interact through standalone applications. Tian serves as co-founder and CEO, while Zhu is co-founder and CTO.
Photon’s core product, Spectrum, is an open-source multi-channel framework for building AI agents that communicate through platforms including iMessage, WhatsApp, Telegram, SMS/RCS and other communication interfaces. Photon also offers hosted infrastructure and developer tooling for operating these agents in production.
The platform combines a unified API, channel framework, command-line tools and observability capabilities. Photon has also developed native messaging functionality including rich media, group conversations and interactive mini apps inside supported messaging experiences.
Gradient said Photon now serves more than 50,000 developers and relays millions of messages per day. Photon has also integrated with developer platforms and frameworks including Vercel’s Chat SDK, which added a vendor-official Photon adapter for iMessage in July 2026.
The company plans to use the Seed capital to advance its product capabilities, expand its developer tooling ecosystem and grow its development team.
