KrokoPay blog
How we think about checkouts, Pix, webhooks and recurring billing. Reasoning and product behavior, with code you can run in the test environment.
Engineering8 min read
Retries, duplicates and events that arrive out of order are not edge cases; they are what at-least-once delivery means. How to build a consumer that verifies, acknowledges fast, processes once and reconciles.
Product7 min read
Recurring billing is not a boolean. It is a small state machine with five states, a handful of events and a lot of product decisions. Here is how to model it, what to do in each state and the mistakes that cost the most.
Payments7 min read
Never shipped Pix before? Here is how it works from the payer's side, why it turns your checkout into a waiting room, which states and events to handle, and how to test the whole flow without moving money.
Product7 min read
Few fields, a total that never moves, one clear method choice, declines explained in plain words and a state for every outcome. A walk through what a payment page must get right, with our own checkout as the example.