How We Handle Webhook Idempotency for Multi-Gateway Environments
One of the biggest challenges in building a balance system is ensuring that a single transaction is only ever processed once. Stripe, LemonSqueezy, and other providers often retry webhooks if they don't receive an immediate 200 OK.
In this article, we dive into how BalancYZ uses a combination of Redis-based locks and database-level transaction uniqueness constraints to ensure that no matter how many times a payment event hits our servers, your client's balance only increases exactly once.
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