Paul Klein IV, founder & CEO of Browserbase, announces their $40M Series B at a $300M valuation led by Notable Capital. Browserbase has raised $67.5M in total funding in just 15 months (!!) since founding the company. Existing investors include big Silicon Valley funds like Kleiner Perkins, CRV, Basecase, and more.

Paul shares how Browserbase is powering the next generation of AI agents and “vibe coders” by providing programmable, cloud-hosted browser infrastructure—what he calls “Twilio for headless browsers.”

Special thank you to John at Strike Capital for the introduction, as well as Bucky Moore and Turner Novak for some incredible questions. This is an awesome interview.

We cover:

* How Browserbase works and real-world automation use cases

* Round dynamics, fundraising strategy & investor support

* Their all-star angel network: Jeff Lawson (Twilio), Patrick Collison (Stripe), Guillermo Rauch (Vercel), founders of Okta, Stitch, WorkOS, and more

* The evolution of their brand (emoji story)

* Go-to-market strategy and scaling past 1,000 customers

* Launching Director.ai for “vibe coders”

* The future of AI agents, authentication, and automation

* Paul’s solo founder journey and team culture in SF

Whether you’re building an agent, automating legacy workflows, or just curious how infra startups are scaling fast in AI, this one’s for you.

Check out Browserbase: https://www.browserbase.com/

Molly on X: https://x.com/MollySOShea

Paul on X: https://x.com/pk_iv

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TIMESTAMPS:

00:00 - Series B Fundraise Announcement

02:21 - Introduction to Browserbase

04:04 - Use Cases & Applications

07:56 - Customer Growth & Product Development

10:48 - GTM & Branding Strategies

22:53 - AI Agent Ecosystem & Authentication

28:08 - AI Regulation & Deep Fakes

30:07 - Launching Director AI

30:54 - Empowering Vibe Coders

33:52 - Customer Service & Team Composition

41:28 - Why Founding a Startup Should Be Last Resort

44:38 - Managing Performance As A Solo Founder

48:38 - Future Outlook & Kalshi Predictions

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