I Built an AI That Talks Like Warren Buffett — Here's What I Learned About Investing

It started with a late-night argument with myself. I was staring at my brokerage account at 11 PM, finger hovering over the "Buy" button for a stock I'd seen mentioned on Twitter three times that day. My rational brain was screaming: "You haven't even read the 10-K." My emotional brain was whispering: "It's going up. You're missing out." I didn't buy. But the experience stuck with me. What if I could have a conversation with someone like Warren Buffett in that moment? Not the real Buffett — but an AI that deeply understands his investment philosophy and could challenge my thinking the way he would? That question led me to build the AI chat feature in KeepRule , and the journey taught me as much about investing as it did about AI engineering. Why Simulate an Investment Master? The investing world has a knowledge problem. Buffett's wisdom is spread across 50+ years of shareholder letters, hundreds of interviews, CNBC appearances, and books written about him. Charlie Munger's mental model