Paris-based Upstream has raised a $3 million pre-seed round backed by Y Combinator, Connect Ventures, and more than 30 founders and operators behind companies including Framer, Algolia, Asana, Alan, and Webflow.
The startup is launching publicly after months in invite-only beta with an inbox designed for both humans and AI agents.
Founded in 2023 by former Algolia and Doctrine executives, Upstream is betting that AI should not simply assist email users.
Email has survived every wave of workplace technology, from instant messaging to collaboration platforms to AI assistants. Yet the way people manage their inboxes has barely changed. Upstream was built by two founders who find that contradiction impossible to ignore.
The Paris-based company has emerged from stealth with a $3 million pre-seed round and the public launch of what it describes as the first inbox built for humans and AI agents simultaneously. The round was backed by Y Combinator, Connect Ventures, and more than 30 founders and operators, including leaders behind Framer, Algolia, Asana, Alan, and Webflow.
