I wanted to figure out how people build payment systems without losing everyone's money. It turns out, my first attempt was a great way to lose a lot of it. I started with what felt like a simple Go service. One endpoint, one database table, and a third-party provider to handle the actual charging. The plan was straightforward: Decode the request. Call the provider to charge the user. Save the res
We are currently witnessing a massive shift in AI development. We’ve moved past the "Chatbot" era and into the era of Agentic Systems—AI that doesn’t just suggest text, but actually executes code, moves money, and modifies databases. However, there is a fundamental architectural flaw in how most agents are built today: we are giving "Intelligence" and "Authority" to the same probabilistic model.
Every AI app I've shipped recently rewrote the same plumbing. The OAuth dance for Slack. Encrypted storage for an API key. Refresh-token logic that finally fails on the 3rd call after an hour. Wiring up an MCP client to a server behind a bearer token someone pasted into a Notion page.
I was reading a Stripe tutorial last week and watched the author write amount: req.body.amount. That single line lets any user buy Premium for $1. It's also a common pattern in Stripe Checkout starter code. This post is about why, and how to make it impossible. You're building a paywalled product. You wire up Stripe Checkout, follow a popular tutorial, ship it. Looks great. Tests pass. Users are p