Back End Heavy Full Stack Developer for AI Startup

We're looking for a backend-leaning full-stack engineer who can take a product from a customer problem all the way through to launch. The ideal person is backend-first but comfortable going full-stack when a feature needs it end-to-end — someone who owns the whole thing rather than handing off and disappearing. We care less about a polished cover letter and more about high internal drive: you don't need a perfectly groomed ticket to start, you see something broken or missing and you go fix it, and you can point to real products you've shipped to real users. You're genuinely curious about the customer's problem, not just the code — you want to understand why someone is struggling, not just close the ticket. And you're AI-native: you're already using AI tools to move faster and have real opinions about how to do it well. This isn't a nice-to-have for us. If that sounds like you, tell us about something you built and shipped end-to-end — what the problem was, what you decided to build, and how it turned out.