Engineering9 min read

The Bug That Taught Me More Than Any Course Ever Did

A race condition in a payment webhook handler sat undetected for 3 weeks. When it fired, it double-charged 4 customers. Here's the full postmortem and why I now test billing code differently.

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By Jason TeixeiraFebruary 1, 2026
DebuggingStripeWebhooksPostmortemLessons Learned
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Quero contar sobre um bug. Não um divertido. Não um engenhoso. O tipo que faz seu estômago embrulhar quando você recebe a notificação no Slack às 23h de uma quinta-feira.

O Que Aconteceu

Eu estava construindo a cobrança por assinatura para a Nexural. Chega um webhook do Stripe —

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Jason Teixeira
Written by
Jason Teixeira
Founder, Sage Ideas Studio · Principal Engineer
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livebuild 5d6c8652026-08-05 06:00Z
// solo studio// no analytics resold// every commit human-reviewed