Hey there! Louis talking. I’m Upstream’s co-founder and CEO.
✨This blog post is part of our Startup & Company Building stories, in which my co-founder Jonathan and I share learnings from our founding journey with Upstream (YC S23). None of this would be possible without our early (dream) team: shoutout to our stars Joseph, Ben, Kostya, Sarah, Patryk.✨
Today, I’d like to answer a question I get asked often as a Paris-based founder who spent 10 years in Tech in San Francisco:
Why did you leave San Francisco to build in Paris?
After ten years in San Francisco (the global epicenter of tech), people are often surprised to hear I left to build my startup, Upstream, in Paris.
It usually goes like this: Why would you leave a place with such momentum, funding, and energy?
It’s a fair question. SF gave me my early wins (and mistakes), my confidence as a product builder, and a priceless network of mentors and teammates. But here’s the truth most people miss:
Why Paris is a founder’s secret weapon
🧠 Paris is home to world class engineering & AI talent
Engineers here are exceptionally skilled, with a long-standing tradition in Mathematics. Global Tech companies such as Meta, Google Deep Mind… have research headquarters in Paris. The kicker? Many don’t realize just how globally competitive they are.
In practice: We hire from all over the world. But talent density in Paris attracts top performers from across the globe. We hired our founding engineers, Kostya and Ben, in Paris. In any other city, they’d be leading a team at a unicorn. In Paris, we were able to build fast with exceptional technical depth.
💸 A dollar in Paris goes twice as far as a dollar in SF
A dollar in Paris stretches twice as far as it does in San Francisco. From office space to comp, you simply get more output per euro.
Bottom-line: We couldn’t have built Upstream this fast or with the same level of craft if we were still in the Bay Area.
🧲 Paris isn’t just romantic; for global talent, it’s magnetic
Paris isn’t just romantic; it’s magnetic. We've attracted and relocated incredible builders, including alumni from top SF startups. It's a city where talent wants to live and work.
In practice: Joseph Calvo was the second designer at Superhuman. He joined us straight from San Francisco as one of our earliest team members. He’s amazingly talented. As a deep lover of craft, I couldn’t dream of a better fit to build the product of our dreams.
💰Our original insight: From 0 product to world class email client in <12 months with just 2 Paris-based engineers
In under 12 months, with just 2 exceptional software engineers, we were able to build and improve upon the UX Gmail spent 20+ years perfecting. We shipped more features, and with deeper polish, than some SF-based teams with 2x the budget do.
And that was before Cursor, Windsurf, and Claude were where they are today :)
In summary: When to choose SF vs. Paris
SF is unmatched if you're just starting out. The bar is high, the feedback is immediate, and you learn by osmosis from the best.
Paris is ideal once you've:
Built something before
Developed your network
Learned how to hire and ship
That’s the sweet spot: You raise in SF, stay plugged in, and build in Paris.
That’s what we’re doing at Upstream.
Are you building outside of SF? I'd love to hear what’s working (and what’s not). Ping me at louis@upstream.do 🐟.
📸 (And yes, there's a pic of me in SF vs. Paris. 🇺🇸 ↔ 🇫🇷)
Why did you leave San Francisco to build in Paris?
After ten years in San Francisco (the global epicenter of tech), people are often surprised to hear I left to build my startup, Upstream, in Paris.
It usually goes like this: Why would you leave a place with such momentum, funding, and energy?
It’s a fair question. SF gave me my early wins (and mistakes), my confidence as a product builder, and a priceless network of mentors and teammates. But here’s the truth most people miss:
Why Paris is a founder’s secret weapon
🧠 Paris is home to world class engineering & AI talent
Engineers here are exceptionally skilled, with a long-standing tradition in Mathematics. Global Tech companies such as Meta, Google Deep Mind… have research headquarters in Paris. The kicker? Many don’t realize just how globally competitive they are.
In practice: We hire from all over the world. But talent density in Paris attracts top performers from across the globe. We hired our founding engineers, Kostya and Ben, in Paris. In any other city, they’d be leading a team at a unicorn. In Paris, we were able to build fast with exceptional technical depth.
💸 A dollar in Paris goes twice as far as a dollar in SF
A dollar in Paris stretches twice as far as it does in San Francisco. From office space to comp, you simply get more output per euro.
Bottom-line: We couldn’t have built Upstream this fast or with the same level of craft if we were still in the Bay Area.
🧲 Paris isn’t just romantic; for global talent, it’s magnetic
Paris isn’t just romantic; it’s magnetic. We've attracted and relocated incredible builders, including alumni from top SF startups. It's a city where talent wants to live and work.
In practice: One of our first hires was the second designer at Superhuman. He joined us straight from San Francisco as one of our earliest team members. He’s amazingly talented. As a deep lover of craft, I couldn’t dream of a better fit to build the product of our dreams.
💰Our original insight: From 0 product to world class email client in <12 months with just 2 Paris-based engineers
In under 12 months, with just 2 exceptional software engineers, we were able to build and improve upon the UX Gmail spent 20+ years perfecting. We shipped more features, and with deeper polish, than some SF-based teams with 2x the budget do.
And that was before Cursor, Windsurf, and Claude were where they are today :)
In summary: When to choose SF vs. Paris
SF is unmatched if you're just starting out. The bar is high, the feedback is immediate, and you learn by osmosis from the best.
Paris is ideal once you've:
Built something before
Developed your network
Learned how to hire and ship
That’s the sweet spot: You raise in SF, stay plugged in, and build in Paris.
That’s what we’re doing at Upstream.
Are you building outside of SF? I'd love to hear what’s working (and what’s not). Ping me at louis@upstream.do 🐟.
📸 (And yes, there's a pic of me in SF vs. Paris. 🇺🇸 ↔ 🇫🇷)
Why did you leave San Francisco to build in Paris?
After ten years in San Francisco (the global epicenter of tech), people are often surprised to hear I left to build my startup, Upstream, in Paris.
It usually goes like this: Why would you leave a place with such momentum, funding, and energy?
It’s a fair question. SF gave me my early wins (and mistakes), my confidence as a product builder, and a priceless network of mentors and teammates. But here’s the truth most people miss:
Why Paris is a founder’s secret weapon
🧠 Paris is home to world class engineering & AI talent
Engineers here are exceptionally skilled, with a long-standing tradition in Mathematics. Global Tech companies such as Meta, Google Deep Mind… have research headquarters in Paris. The kicker? Many don’t realize just how globally competitive they are.
In practice: We hire from all over the world. But talent density in Paris attracts top performers from across the globe. We hired our founding engineers, Kostya and Ben, in Paris. In any other city, they’d be leading a team at a unicorn. In Paris, we were able to build fast with exceptional technical depth.
💸 A dollar in Paris goes twice as far as a dollar in SF
A dollar in Paris stretches twice as far as it does in San Francisco. From office space to comp, you simply get more output per euro.
Bottom-line: We couldn’t have built Upstream this fast or with the same level of craft if we were still in the Bay Area.
🧲 Paris isn’t just romantic; for global talent, it’s magnetic
Paris isn’t just romantic; it’s magnetic. We've attracted and relocated incredible builders, including alumni from top SF startups. It's a city where talent wants to live and work.
In practice: Joseph Calvo was the second designer at Superhuman. He joined us straight from San Francisco as one of our earliest team members. He’s amazingly talented. As a deep lover of craft, I couldn’t dream of a better fit to build the product of our dreams.
💰Our original insight: From 0 product to world class email client in <12 months with just 2 Paris-based engineers
In under 12 months, with just 2 exceptional software engineers, we were able to build and improve upon the UX Gmail spent 20+ years perfecting. We shipped more features, and with deeper polish, than some SF-based teams with 2x the budget do.
And that was before Cursor, Windsurf, and Claude were where they are today :)
In summary: When to choose SF vs. Paris
SF is unmatched if you're just starting out. The bar is high, the feedback is immediate, and you learn by osmosis from the best.
Paris is ideal once you've:
Built something before
Developed your network
Learned how to hire and ship
That’s the sweet spot: You raise in SF, stay plugged in, and build in Paris.
That’s what we’re doing at Upstream.
Are you building outside of SF? I'd love to hear what’s working (and what’s not). Ping me at louis@upstream.do 🐟.
📸 (And yes, there's a pic of me in SF vs. Paris. 🇺🇸 ↔ 🇫🇷)
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🧠 FAQ
Q: Is SF still relevant in 2025?
Absolutely. But it’s no longer the only place to build. Talent is now global, and so are capital markets.
Q: Isn’t hiring harder outside of Silicon Valley?
It depends. In Paris, we find that talent is abundant- especially if you're technical and can inspire with your vision. Plus, fewer startups means less hiring noise.
Q: Can you raise capital from Paris?
Yes. We’ve seen success with US investors who care more about execution than your GPS coordinates.
Q: Why not Berlin/Lisbon/Barcelona?
All great hubs. Paris just happens to combine top-tier engineering, investor interest, and world-class lifestyle. And Jon my co-founder & I are French 🤪