San Francisco June 2026: What startups are building
I came back to SF after some months and packed my schedule with VC and founder meetings and the YC Demo Day.
I' am more bullish than ever about tech and startups.
This is what I’ve learnt this week in SF:
Attio is the AI CRM that compounds revenue around the clock.
It gives your team the foundation for moving fast, staying sharp, and scaling without breaking. Every customer signal, from emails and meetings to product usage, billing, support, and agent activity, is synced from day one, giving you a live picture of every account.
With Attio, you’ll get:
Revenue agents, workflows, and automations across every stage of your motion
Instant answers to anything you Ask Attio about your business
Access to your customer data wherever you work, through Attio’s MCP, API, and App SDK
30,000+ teams use Attio to drive more revenue at scale. Are you one of them?
The pull SF has from top talent is something that doesn’t happen anywhere else in the world. The most ambitious founders come here to build.
We went by to say hi to Alberto and Alejandro Rosas, the founders of Didit, a YC startups that just closed a 7.2M round and is growing extremely fast right now. Their work ethic and ambition level is crazy. They are competing to win and don’t take a no for answer.
To keep the YC drive and ambience they rented an office space together with other 3 YC startups and are working 7 days a week.
The most ambitious VCs follow the most ambitious founders, so every VC that wants to build global has some type of presence here.
We just went by to say hi to our friends from Creandum, who recently opened up a new office in South Park. Creandum is one of my favorite european VCs, they’ve funded multiple unicorns in Europe and now are competing in the big leagues.
It’s understated how hard it is to do what they’ve achieved.
Density is everywhere. Speed is why things work
I went to Cafe Okawari to grab some lunch and bumped into one of my friends from xAI and another friends that used to work as an investor in a16z and is now a founder. Crazy
Big ideas are rewarded: where in Europe thinking big means being delusional. In SF big ideas attract bold investors.
I invested in Apollo Atomics (will write in detail about it soon). They are making nuclear reactors dramatically more compact, factory-buildable, transportable by truck, and deployable on a timeline customers actually need.
I’ve never been more impressed by a founder than by Assil Halimi and Drew Walker 🔥
The question: is this ecosystem replicable in Europe? Will there ever be an European YC?
Cheers,Guillermo
Stop reading and start building
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