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BaseLayer - Ep 3: Shane Mac (Co-founder, XMTP)

BaseTue, Dec 9, 2025, 12:00 AM

Shane Mac was one of the first developers on Twitter. He built a company to 100 million users, got acquired by BlackBerry, and had Zuckerberg demo his Facebook Messenger chatbot at F8. Then the platforms changed the rules. API changes. $500K/month fees. After 15 years of building on 'quicksand,' Shane co-founded XMTP, a decentralized messaging protocol built on Base that no one can shut down. In this episode of BaseLayer, Shane shares: • Starting as an eBay power seller at 13 • Being one of the first Twitter developers • Growing to 100M users and the BlackBerry acquisition • Why the open internet died • Building XMTP on Base • "Think smaller to build bigger" Follow Shane: https://x.com/ShaneMac Follow XMTP: https://x.com/XMTP_

Transcript

My name is Shane Mack. I'm from Pory, Illinois and I'm the co-founder of XMTP. I'll never forget it. I was 13 years old and I didn't know what being an entrepreneur was. I didn't know what a business was.

I was a baseball player and all my friends had their old bat from the last year laying around and these bats were like $179. And at that moment was right when eBay was happening. And I remember I made an eBay account and I had a power seller badge and I bought this printer at home that printed out the FedEx labels. And I asked my buddy if he would sell me his bat from the last year. And he was like, "Sure."

And I was like, "2 bucks." And he's like, "Great." I put it on eBay. $179, $49.99 shipping and handling.

It sold. I was selling actually like 10, 20, 30 bats a month. And funny story, my first tech experience years years later, I go into the board meeting and the new investor and person that might join our board is Meg Whitman, the CEO of eBay. And I brought my little my little plaque I got when I was 14 years old that says, "Thanks for being an eBay power seller signed by me." And I brought it to her and she's like, "You have no idea how powerful it is to really celebrate the community and let them know how much we care about them and how important that was to the early days of eBay."

I've always been since I was a sophomore in college obsessed with communication, connecting with people online. And for me, what I realized was crypto could help solve that problem. I remember my dad would always say to me like, I think you should probably get in the trades. Messaging 23232 doesn't feel like it's going to be important to the world. And I was one of the first developers ever on Twitter in 20067.

It was still an SMS protocol. And I was like, I can text anybody in the world. sitting there talking to the original founders and community on Twitter and I'm in this little town in Mcome Illinois and the idea that I some little kid from a little town and knows nobody can talk to anybody was the moment that changed the power of the internet and then for the next 15 years I built on top of those platforms. We grew to 100 million people in two years at our first startup and then BlackBerry acquired us and I worked on BBM. the next company.

We were the first to ever launch a chatbot selling flowers on Facebook Messenger in 2014 and Zuckerberg demoed it at the, you know, F8. And what I realized is that I was building on top of Quicksand every single time. I was their best partner until I got cut off. I was their best partner until they changed the API. I was a best partner until they charged us $500,000 a month to keep using it.

And I realized the open internet had died. XMTP is a decentralized messaging network and it's an open protocol where anyone can build on top of it and no company or person can take away our communication as a user. You know, our mission at XMTP is to increase the world's freedom to communicate. Privacy is a human right for everyone on Earth. I think is a really important thing.

And I believe the only way to do that is to make sure that no one can turn off one centralized server and kill it for all of us. At XMTP, the reason we love building on base is cuz we're all part of a bigger story. And what I think is happening is Ethereum is the world's computer, base is the global economy, and XMTP is the messaging economy. And when these things come together, we are laying the foundation for the next internet to be all based on open protocols. When I think about XMTP in 5 years, I think about being the largest secure messaging protocol in the world.

And the reason is because people can trust it. I think the most counterintuitive thing that is hard to learn is to think smaller to build something bigger. I always think about sitting at a dinner table. And can you tell the six people at the dinner table what you do in one sentence? Can you show it to them?

Can they understand it? Can they use it? Do they think it's magical? Hey, I'm Shane Mack. I'm the co-founder of XMTP and I'm building on base.

Automatic transcript — names and jargon may be misspelled.