He Built, Launched, and Sold a Company in 20 Hours. Now He’s Inside Downing Street

The first time I met David in person was at Slush in Helsinki last year.

Other than being a really helpful, genuine guy, he felt like someone operating at a different tempo to most.

David has built across AI, venture, and community, from Warestack to Unicorn Mafia to the20hr, the company built, launched, and sold in under 20 hours. He now also sits inside No10, helping ship AI tools into government.

At a time when much of Europe still talks more than it builds, David belongs to a set of operators testing what speed, ambition, and execution can actually look like in practice. Across hackathons, founder communities, venture work, and public-sector deployment, he seems less interested in theory than in making things real.

I sat down with David to talk about building at speed, spotting breakout founders early, and why the UK still has a real shot at becoming the best place in the world to build.

Q&A

Q: You seem to operate at a very unusual pace. Where does that come from, and how much of it is mindset versus system?

A: I think it's mostly just intolerance for friction. I find slowness genuinely uncomfortable - not in a stressed way, more like when you're watching someone take forever to make a point you figured out three sentences ago. The system stuff helps - I'm pretty ruthless about what I actually spend time on - but the underlying thing is just caring a lot about making things real. Theory without output bores me. So I move.

Q: From T1V to Unicorn Mafia to the20hr, your work spans company building, community, and venture. What ties those worlds together for you?

A: Access. Every single one of those things is about getting talented people closer to the resources, deals, or opportunities they should already have but don't. Unicorn Mafia is that for builders. T1V is that for investors who can't touch pre-IPO markets, and for startups who deserve better capital or better tech than they're getting. The20hr was a statement - proof that Europeans can move as fast as anyone on the planet, that the glass ceiling on ambition and execution here is self-imposed. We came to make noise and do something that hadn't been done before.

Q: The20hr became a kind of symbol of extreme execution. Beyond the headline, what did that experiment actually teach you about speed, conviction, and building under pressure?

A: The main thing was how much time most people spend building consensus instead of building product. We just... didn't do that. One person decided, we moved. And it worked. What it exposed was that a lot of startup slowness is social, not technical. The other thing - and this surprised me - is that constraints are clarifying. When you have 20 hours you can't afford to be precious. You find out very quickly what actually matters.

Q: You spend a lot of time around ambitious founders very early. What signals tell you someone has breakout potential before the rest of the market sees it?

A: We're drowning in tick-boxers right now. Founders who've figured out the formula - get the right angel on the cap table, pitch the right vision, get into the right accelerator - and are optimising for the badge rather than the thing. That's not building, that's cosplaying. So the first signal for me is someone who's just... doing it. Not after they raise, not once they get into YC - right now, scrappily, because they can't not.

The second is how they respond to pushback. The tick-boxers get defensive because they're protecting a narrative. The real ones get more specific - they've thought about it harder than you have and they know it.

And the last one is how they talk about their users. Whether they're genuinely fascinated by them as people or just tracking them as numbers. The best founders I've met find their users interesting. That curiosity is usually what makes the product actually good.

The common thread is self-worth that doesn't depend on external validation. They're not chasing shortcuts because they don't need the shortcut to believe in what they're doing.

Q: The UK startup ecosystem has no shortage of talent, but it still does not always convert that into enough category-defining companies. What do you think is still missing?

A: Permissioning. People here wait to be told they're allowed - allowed to raise, allowed to scale, allowed to call themselves a real company. And it goes deeper than that: they want the roadmap too. The advisor, the accelerator, the next step handed to them. But the struggle of figuring it out yourself with no template and no one to ask - that's not the obstacle, that's the point. That's where you find the insight that's actually yours, the thing no one could have advised you on anyway.

The talent is here. The risk appetite is improving. But there's still this gravitational pull toward the sensible path, and the social cost of failure feels higher than it should. The founders who break out here tend to have either lived abroad, or just never got the memo.

Q: If you were trying to make the UK the best place in the world to build over the next five years, where would you start?

A: I'd drop the "trying." We're doing it. The system is set, the pieces are there, and frankly we're out of excuses. The last few years were about making the case - now it's money time.

I'm embedded inside government specifically to close the remaining gaps. We're bringing the best people in the country into the public sector to ship better, faster, smarter tech. Government procurement, legacy systems, the friction points that have slowed startups down for years - we're working on them from the inside. No other nation is doing this.

If anyone's hitting walls with any of this - genuinely, reach out. But honestly? We're done making the case. Time to build.

Q: Finishing off with a YC-classic; do you have a “Requests for Startups”-list yourself? Mind sharing some?

A: No. And honestly I think the whole concept is a bit counterproductive. The second you publish a list of what to build, you're just generating more tick-boxers - founders who'll reverse-engineer the brief instead of following their own obsession. That's the opposite of what creates anything interesting.

My only request is: build. Succeed, fail, pivot, burn it down and start again - none of that matters as much as the fact that you're following something that's genuinely yours and pushing it as far as it'll go. The breakthroughs don't come from someone else's roadmap. They come from people who were so convinced of something that they couldn't not do it.

Any list I give you is a ceiling. I'd rather you didn't have one.