Dear friend,

You are running a small business. You may not call it that.

You drive for DoorDash on Mondays, Uber on Wednesdays, Spark on the weekend. You buy gas with your card. You buy a phone mount, a hot bag, a cooler. You pay platform fees and bank fees and a phone bill. You earn money. You spend money. You file a 1099. That is a business. And you are leaving thousands of dollars on the table every year because the tools that file your taxes were built for someone else's job.

We are building Sourdough to fix that.

When you connect your bank, an AI agent reads every line — every swipe, every deposit. It knows the IRS rules. It tags each line with the part of the tax code it falls under. At the end of the year you tap one button and your taxes are filed: federal and state, deductions found, citations attached.

Ninety-nine dollars a year. One tap.

I built and sold a small bank for nurses (Lume, YC S20, sold to Vivian Health, an IAC company). I spent 2018 building the receipt-matching engine at AppZen that this is patterned on. For the last three weeks I have driven on every major gig platform and talked to a hundred and twelve of the people we are building this for. They were all leaving money behind. Every one.

Tax filing is the starter. The categorized ledger is the loaf.

If you are a gig worker who would like to be early, write to hello@sourdough.tax. I read everything that comes in.

If you are an investor, a partner, or someone who'd just like to talk: shantanu@sourdough.tax.