BREAKING  Kernel raises $22M to power browser infrastructure for AI agents Led by Accel with Y Combinator, Vercel Ventures & SV Angel Angels include Paul Graham, Solomon Hykes, David Cramer & Charlie Marsh 3000+ teams building agents on Kernel Production users include Cash App & Rye Cold starts in under 150ms · SOC 2 · HIPAA-ready BREAKING  Kernel raises $22M to power browser infrastructure for AI agents Led by Accel with Y Combinator, Vercel Ventures & SV Angel Angels include Paul Graham, Solomon Hykes, David Cramer & Charlie Marsh 3000+ teams building agents on Kernel Production users include Cash App & Rye Cold starts in under 150ms · SOC 2 · HIPAA-ready
Company Profile AI · Developer Tools San Francisco Founded 2025
Browsers-as-a-Service

Kernel.

The company that runs the browser so your AI agent doesn't have to - booting cloud browsers in milliseconds, keeping them logged in, and getting them past the bot detectors.

Kernel logo - green rounded wordmark

The green wordmark, sitting on cream: friendly-looking plumbing for a very serious job. Infrastructure that would rather you never notice it.

$22M
Seed + Series A
<150ms
Browser Cold Start
3000+
Teams Building
2025
Founded · YC S25
The Story

Browsers for robots, essentially

Here is a fact about artificial intelligence that does not make it into the keynote: the smartest model in the world is useless if it cannot log into your bank. Large language models can reason, plan, and write code, but the actual internet - the one with cookies, CAPTCHAs, two-factor prompts, and websites that quietly decide you are a robot - was built for humans clicking with a mouse. When you want an AI agent to book a flight, reconcile an invoice, or pull data from a portal that has no API, it needs to do what a person does: open a browser and use the web. Kernel's entire business is that unglamorous sentence.

Kernel sells browser infrastructure as a service. A developer building an agent calls Kernel, and Kernel spins up a real browser in the cloud - the company says in under 150 milliseconds - hands it over, keeps it logged in across workflows, routes it through residential proxies so sites don't flag it, records the session for debugging, and tears it down afterward. The developer never has to operate a fleet of browsers, which turns out to be one of those problems that is boring to describe and miserable to run.

This is a classic infrastructure bet, and infrastructure bets have a certain shape. You find a job that everyone building on top of you will need and nobody wants to do themselves, you do it faster and more reliably than they could, and you make it disappear. Content delivery networks did this for web pages. Payment processors did it for credit cards. Kernel is trying to do it for the moment an AI agent touches the live internet - a layer the industry has started calling, plainly, the "browser layer."

"LLMs make it possible to automate any work done on a computer. Kernel fills this gap - letting developers spin up browsers in milliseconds, persist state across workflows, and build agents that securely handle user credentials." Catherine Jue, Co-Founder & CEO

The pitch works because of a slightly counterintuitive claim about the future: the browser is not going away, even when the users are machines. You might expect that agents would prefer clean APIs to messy web pages, and sometimes they do. But most of the world's software still lives behind a login screen and a rendered page, and rewriting all of it for robots is not on anyone's roadmap. So the agents will keep using browsers, the way everyone else does - which means someone has to run those browsers well. Kernel is betting it is that someone.

What makes the layer hard is the part customers care about most: it has to be fast, and it has to not get caught. Latency is a tax on every single action an agent takes - a slow browser makes a slow agent, and a slow agent is an expensive one. Kernel's answer is to build on lightweight, isolated virtual machines (the kind of unikernel-style approach that lets you pre-warm and boot in a blink) so cold starts are measured in milliseconds rather than seconds. Meanwhile, the modern web is an arms race of bot detection, and an agent that gets blocked is an agent that failed. Kernel bundles stealth mode, residential proxies, and automatic CAPTCHA solving so the browser reads as a person, not a script.

Then there is the quieter, more valuable feature: trust. Kernel is SOC 2 compliant and HIPAA-ready, which sounds like a checklist and is actually a business model. Those certifications are what let a company like Cash App put agent workloads into production instead of a demo. The named customers - Cash App, the commerce API company Rye, and a long tail of Y Combinator-backed startups - matter less as logos than as proof that the plumbing holds under real load.

Under the Hood

What you can actually do with it

Launch

Millisecond browsers

Spin up managed cloud browsers that launch and connect fast - the company cites sub-150ms cold starts - so agents don't wait on their tools.

Persist

Stay logged in

Persistent sessions retain cookies and authentication, letting agents resume workflows and securely handle credentials across runs.

Evade

Stealth mode

Anti-bot detection, residential proxies, and automatic CAPTCHA solving so agents reach sites that block ordinary scripts.

Observe

Live view & replays

Watch a browser run in real time, then replay the session with full logging to debug exactly what an agent did.

Integrate

Framework-native

Works with Playwright, Puppeteer, CDP, and agent frameworks like Browser Use - drop it into an existing stack.

Open

Open source & CLI

Open-source browser images and a CLI on GitHub, plus autoscaling and isolated VMs for production workloads.

The Operators

Who's building it

Co-Founder & CEO

Catherine Jue

Previously a co-founder at Sway Finance (S16). Sets Kernel's thesis that anything done on a computer can now be automated - and that the browser is the interface where that happens.

Co-Founder & CTO

Rafael Garcia

Previously co-founder and CTO of Clever (S12), an education software company with a roughly $500M exit. A second infrastructure bet, this time aimed at AI agents.

Two founders, a Y Combinator Summer 2025 badge, and a team of roughly a half-dozen when the round closed. Small on purpose - infrastructure companies tend to stay lean until the load forces them not to.

Follow the Money

The $22M round

RoundAmountAnnouncedLead
Seed + Series A (combined)$22,000,000Oct 9, 2025Accel
Accel — lead Y Combinator Cintrifuse Capital Vercel Ventures Refinery Ventures SV Angel Paul Graham Solomon Hykes David Cramer Zach Sims Charlie Marsh
When the people who built Docker, Sentry, and Astral all write checks into the same seed, it is worth noting what they have in common: each shipped infrastructure a generation of developers came to depend on. On Kernel's angel list
Milestones

A short, fast history

2025

Kernel is founded

Catherine Jue and Rafael Garcia start Kernel in San Francisco to build browser infrastructure for AI agents.

2025 · Summer

Y Combinator S25

Kernel joins YC's Summer 2025 batch while building its browsers-as-a-service platform.

2025 · October

$22M raised

The company announces combined seed and Series A funding led by Accel to scale the platform for AI's browser layer.

The Field

Who else is running browsers

The most-cited alternative is Browserbase, and Kernel has written openly comparing itself on speed. Beyond that, the field includes Steel, Browserless, and Hyperbrowser - plus the default option every team starts with and eventually regrets: running your own Playwright or Puppeteer fleet.

That last competitor is the important one. Most infrastructure companies aren't fighting a rival so much as fighting "we'll just build it ourselves." Kernel's job is to make the build-it-yourself path look like exactly what it is: a browser fleet you now have to babysit forever, instead of the agent you actually wanted to ship.

Questions

The obvious ones, answered

What does Kernel do?

Kernel provides browser infrastructure as a service - cloud browsers that AI agents and automations use to interact with the web, with fast spin-up, persistent login sessions, and anti-bot stealth features.

Who founded Kernel and when?

Kernel was founded in 2025 by Catherine Jue (Co-Founder & CEO) and Rafael Garcia (Co-Founder & CTO), and is based in San Francisco.

How much has Kernel raised?

$22 million in combined seed and Series A funding, announced in October 2025 and led by Accel, with Y Combinator, Vercel Ventures, SV Angel and others participating.

Who uses Kernel?

The company says thousands of teams build agents on its platform, with named production users including Cash App, Rye, and many Y Combinator-backed startups.

Why not just run my own browsers?

Kernel handles the hard parts - millisecond cold starts, headless/headful modes, residential proxies, CAPTCHA solving, session persistence, and debugging - so you don't build and operate a browser fleet yourself.

Go Deeper

Links, demos & social

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