The duplicate charge that taught me idempotency
A handful of customers were charged twice for the same gold purchase. The bug wasn’t in our payment code — it was in the assumption that only one thing would tell us the payment had succeeded.
Writing on payments, mobile performance, and shipping full-stack products.
Most of what I write comes out of something that broke in production and the week I spent understanding why. Collected here in chronological order.
What RAG actually earned us in eCommerce
I put a retrieval-augmented recommendation layer into a storefront and conversions went up 40%. Almost none of that came from the language model — it came from the retrieval, which is the half nobody wants to talk about.
Cutting friction out of a mobile checkout
Our checkout wasn’t slow in any way a profiler would show you. It was slow in the way a user feels — too many taps, too many moments of not knowing what was happening. Here’s what actually moved the numbers.