Pinned Tweet
Almost 5 years ago, after one of our first trader events, I joked to @luanalopeslara that working at Kalshi felt like a class project. The team was tiny but motivated, and our most passionate traders could fit with us in our cramped SoHo office.
$40B later, our relationships with each other, our product, and our traders feel just as close. There are just a lot more of us now.
Back then I had a quiet deference for large institutions. When we started working with partners much bigger than us, I honestly wasn’t sure we could bring event contracts mainstream without them.
Along the way, I watched companies that looked untouchable come and go, and I watched us keep building. Today we're right alongside the giants I once feared we couldn’t do it without.
What I’ve learned is that every great company starts as an underdog. Up close, even the biggest ones are just people you can admire, learn from, and compete with.
These days, one of my favorite things is walking around the city in my Kalshi hoodie and meeting people who tell me how much they love our product. It never gets old.
None of this happens without our community or the people who have joined this team to make Kalshi better for them. I’m grateful for both, and we’ll never take either for granted.
@mansourtarek_, you wrote that we believed when there was little to point to. Believing was the easy part. You and Luana gave us something to believe in.
We’re still growing, and it still feels like that night in SoHo. Come see for yourself.
Kalshi just raised an additional $1B, valuing the company at $40B. This will help us expand into stocks, compute, indices, and institutional.
Tomorrow marks 8 years since we got accepted into YC and the journey began.
The odds of a kid from Lebanon getting here were pretty low.
Growing up there was great, but very challenging. We went through war. We had bombs explode in front of my house. I watched brilliant people’s lives destroyed for reasons beyond their control.
Lebanon is an unpredictable country. That unpredictability made it hard to plan for success. And yet despite it all, my mom sacrificed everything to give me and my brother the chance to go back to the US.
I found my refuge in two things: anime and math. Especially math.
I loved math because it calmed me. It was the opposite of unpredictable: clear, deterministic, orderly, and consistent. The proof is either right or wrong. I find that elegant and beautiful.
I was lucky.
I made it to my dream school, MIT (largely thanks to my mom), and my love for math quickly translated to a love for statistics, probability, and markets.
I love markets for a lot of the same reasons. Their incentives are clear: you get rewarded for being right and for pursuing knowledge. They are effective weighting machines for people’s opinions. They provide an incentive to be truthful, because they separate good information from bad information. They let people challenge the consensus and be rewarded for being right.
IMO, Hayek, Surowiecki, Hanson, Tetlock were the founding fathers of prediction markets. The more I read them, the more obsessed I got with the idea of applying market-based pricing to more things.
Markets bring rigor and critical thinking to more questions. And in an increasingly polarized and information-positioned word, I believe we need that more than ever.
Markets would also let people predict and manage more things outside of their control. And the world was becoming increasingly more unpredictable, and more like Lebanon, not less.
That love for markets got Luana and me to build Kalshi.
At first, it was mostly an idea we couldn’t stop talking about. We didn’t have much money. Luana’s sister bought the Kalshi domain name for us (for ~$1.7k). We moved to SF to get started, and embarked on a long, uncertain journey to build a regulated exchange.
The paranoia and anxiety from my childhood never left me. Even when things are going well, I think about what could go wrong. When people trust you with their money, that instinct serves a purpose.
I wanted us to build something that would hold up under pressure.
The first principle we defined at the company: regulatory-first. We worked with regulators for years before we listed a single market. We took every step to do things the right way and always asked for approval before proceeding. It was very hard at times, especially when we were being overtaken by competitors, but we believe doing things the right way matters.
Luana and I aren’t the only ones.
Our team put years of their lives into something far from certain. That’s especially true of Lior, Brandon, Rainer, Luis, Xavier, and Josef, who stuck with us for years. They believed when there was little to point to. And they stuck with us no matter how long it took. Kalshi is the result of an arduous journey through a long desert where, at times, most people didn’t understand why we were making the walk.
Many people still don’t understand what we’re doing and some disagree with us. Markets have historically taken time to be understood and accepted by some. But while not always obvious, their benefits are vast: capital markets help allocate capital and derivative markets help predict and manage uncertainty.
I firmly believe in these benefits, and that’s why I am dedicating my life to building this market.
Markets have caused issues many times in the past, and they certainly can present harms (manipulation, insiders, and addictive behaviors). These harms are more acute for certain types of markets (sports, short-term options, etc.) than others. It’s why I believe that guardrails need to exist and why we have taken the approach we have taken. We have consistently prioritized thinking critically about the risks and building the appropriate safeguards, sometimes beyond what the regulators require us to do. Many believe more needs to be done, and that’s a conversation I welcome.
Over time, I believe more people will see what we see: markets can help us get smarter and manage the future with more rigor, more precision, and more certainty than we have today.
To our tens of millions of users: you have made Kalshi bigger than anything Luana and I could have possibly imagined. Thank you for trusting us and thank you for coming along on the journey. I feel a strong responsibility to build a company worthy of that trust.
I am so lucky to spend my life building something I love. I hope everyone finds something they care about that much. Something that keeps you curious. Something that pushes you to your limits. Something that may put you at odds with the status quo. Something worth the hard days.
For me, it’s still markets. The more I learn, the more I want to understand.
rainer 🇭🇹🌹🌱 retweeted
Single stock perps (SSPs) are here. And they're a truly great product. You don’t need to pay rollover fees like with futures, they’re simpler to trade than options, and you can go short just as easy as you can go long.
This is one of the most consequential products we’ve launched and I couldn’t be more proud of the team that worked for over a year to bring them to life. Just this morning, since the stealth launch, our users traded over $300m.
Grateful to be the ones bringing these to America in a regulated way 💚
rainer 🇭🇹🌹🌱 retweeted
I first heard about Kalshi as a senior in college, 6 years ago, and I loved the idea immediately: I felt like prediction markets solved an urgent need in the world. But I still wasn’t sure that joining the company was the right next step for me. Instead of going to a ~10 person startup, I could instead take a job at a big tech or trading firm.
My view changed as soon as I met the team: everyone I spoke to - among them @mansourtarek_ , @luanalopeslara , @luishusier , and @_rainerds - was so passionate, curious, and thoughtful. It became clear to me that even if the company didn’t succeed - if I gave it my all, I could learn a lot by working with such talented people.
Kalshi has had its ups and downs, but that first impression has held true for every day of my last 6 years. Remarkably, as we’ve grown, the challenges have grown too. I have felt at times incredibly stressed, but that all is 100x easier to bear with the right people around you and the knowledge that you’re working through difficult, worthy problems together.
With an announcement like this one, it’s easy to look back in hindsight and say that I made the right choice. But I’d feel the same way even if today’s news was very different, and we were still 10 people grinding away.
I’m so grateful for having had the opportunity to build with this team, and I look forward to many more years and even tougher problems to solve together. If you’re interested in joining us, send me a message!
“It's a dangerous business, Frodo, going out your door. You step onto the road, and if you don't keep your feet, there's no knowing where you might be swept off to.”
Kalshi just raised an additional $1B, valuing the company at $40B. This will help us expand into stocks, compute, indices, and institutional.
Tomorrow marks 8 years since we got accepted into YC and the journey began.
The odds of a kid from Lebanon getting here were pretty low.
Growing up there was great, but very challenging. We went through war. We had bombs explode in front of my house. I watched brilliant people’s lives destroyed for reasons beyond their control.
Lebanon is an unpredictable country. That unpredictability made it hard to plan for success. And yet despite it all, my mom sacrificed everything to give me and my brother the chance to go back to the US.
I found my refuge in two things: anime and math. Especially math.
I loved math because it calmed me. It was the opposite of unpredictable: clear, deterministic, orderly, and consistent. The proof is either right or wrong. I find that elegant and beautiful.
I was lucky.
I made it to my dream school, MIT (largely thanks to my mom), and my love for math quickly translated to a love for statistics, probability, and markets.
I love markets for a lot of the same reasons. Their incentives are clear: you get rewarded for being right and for pursuing knowledge. They are effective weighting machines for people’s opinions. They provide an incentive to be truthful, because they separate good information from bad information. They let people challenge the consensus and be rewarded for being right.
IMO, Hayek, Surowiecki, Hanson, Tetlock were the founding fathers of prediction markets. The more I read them, the more obsessed I got with the idea of applying market-based pricing to more things.
Markets bring rigor and critical thinking to more questions. And in an increasingly polarized and information-positioned word, I believe we need that more than ever.
Markets would also let people predict and manage more things outside of their control. And the world was becoming increasingly more unpredictable, and more like Lebanon, not less.
That love for markets got Luana and me to build Kalshi.
At first, it was mostly an idea we couldn’t stop talking about. We didn’t have much money. Luana’s sister bought the Kalshi domain name for us (for ~$1.7k). We moved to SF to get started, and embarked on a long, uncertain journey to build a regulated exchange.
The paranoia and anxiety from my childhood never left me. Even when things are going well, I think about what could go wrong. When people trust you with their money, that instinct serves a purpose.
I wanted us to build something that would hold up under pressure.
The first principle we defined at the company: regulatory-first. We worked with regulators for years before we listed a single market. We took every step to do things the right way and always asked for approval before proceeding. It was very hard at times, especially when we were being overtaken by competitors, but we believe doing things the right way matters.
Luana and I aren’t the only ones.
Our team put years of their lives into something far from certain. That’s especially true of Lior, Brandon, Rainer, Luis, Xavier, and Josef, who stuck with us for years. They believed when there was little to point to. And they stuck with us no matter how long it took. Kalshi is the result of an arduous journey through a long desert where, at times, most people didn’t understand why we were making the walk.
Many people still don’t understand what we’re doing and some disagree with us. Markets have historically taken time to be understood and accepted by some. But while not always obvious, their benefits are vast: capital markets help allocate capital and derivative markets help predict and manage uncertainty.
I firmly believe in these benefits, and that’s why I am dedicating my life to building this market.
Markets have caused issues many times in the past, and they certainly can present harms (manipulation, insiders, and addictive behaviors). These harms are more acute for certain types of markets (sports, short-term options, etc.) than others. It’s why I believe that guardrails need to exist and why we have taken the approach we have taken. We have consistently prioritized thinking critically about the risks and building the appropriate safeguards, sometimes beyond what the regulators require us to do. Many believe more needs to be done, and that’s a conversation I welcome.
Over time, I believe more people will see what we see: markets can help us get smarter and manage the future with more rigor, more precision, and more certainty than we have today.
To our tens of millions of users: you have made Kalshi bigger than anything Luana and I could have possibly imagined. Thank you for trusting us and thank you for coming along on the journey. I feel a strong responsibility to build a company worthy of that trust.
I am so lucky to spend my life building something I love. I hope everyone finds something they care about that much. Something that keeps you curious. Something that pushes you to your limits. Something that may put you at odds with the status quo. Something worth the hard days.
For me, it’s still markets. The more I learn, the more I want to understand.
rainer 🇭🇹🌹🌱 retweeted
Yes, a bet and a trade often look similar.
But how they work is fundamentally different.
A sportsbook sets the odds and takes the other side of your bet. Prediction markets are markets, where buyers and sellers compete to discover and produce efficient prices and enable important public benefits.
What the market is about can change, but the structure doesn't.
My op-ed on prediction markets and regulation:
rainer 🇭🇹🌹🌱 retweeted
The NBA has partnered with Kalshi as a Preferred Prediction Market Exchange.
Official NBA data to settle trades, stronger safeguards, and NBA branding on Kalshi.
Fans come to Kalshi because open markets are a fairer way to trade basketball. Now, it’s Official.
rainer 🇭🇹🌹🌱 retweeted
Election integrity is important. That is why is time that Congress (and state congresses) turns it attention to regulating polls. Not prediction markets, polls. (1/n)
politico.com/news/2026/10/22…
rainer 🇭🇹🌹🌱 retweeted
Malika: "You're willing to take less (money)?"
KAT: "Oh yeah, because I want this team to stay together. That's always been my main priority was to keep everyone here, to keep this core, this special team that we have. So it was the first thing on my mind as soon as it was. And there was nowhere in my mind a max was even thought of"
Jalen to KAT: "Sign the contract" 😁
rainer 🇭🇹🌹🌱 retweeted
Thank you for having me @CBSLosAngeles to speak about prediction market hedging!
Many speculate (or "bet", as you call it) on prediction markets, just like they do on any derivatives market. But the exchange structure harnesses that speculation for price discovery and enables risk management for individuals and businesses, big or small.
Over time, prediction markets will let people manage exposure to most things outside of our control. We're in the early innings of that. Incredibly excited to be part of building that future.
rainer 🇭🇹🌹🌱 retweeted
Hello everyone! This is Sandra Brunson, @jalenbrunson1’s mom. Usually, I send my son a text message before every game.
But tonight he gets his championship ring!
So I wrote him this letter. theplayerstribune.com/sandra…
rainer 🇭🇹🌹🌱 retweeted
I was in the building and this never gets old.
These are the plays that went against us for at least 40 years. macri couldn’t believe it. “When he said this is so fucked up—he’s still thinking we’re gonna lose while hoping we win” you see almost no reaction after the OG tip.
All bottled up 40 years came out.
The other shoe didn’t drop. We won. 💙🧡✋🏽🏆
rainer 🇭🇹🌹🌱 retweeted
What type of people are successful on Kalshi?
We commissioned an independent third party to study our top traders. Here’s what they found:
Top traders are not limited to privileged or financial backgrounds.
-79% went to public school
-They are over 2x as likely to have worked retail or service jobs than on Wall Street
-65% are self-taught
The majority of top traders: :
-Actively seek out primary documents for research
-Actively seek out conflicting sources to challenge their beliefs
-Outperform the public on numeracy tests
The findings echo the foundational work of Philip Tetlock: the best forecasters are not subject matter experts. They tend to be otherwise-ordinary people who are intellectually humble, willing to do research, and think probabilistically instead of emotionally.
