Your Card Declined Because Your Server Was Too Slow

Stripe gives you exactly two seconds to approve every card swipe. Miss that window and the transaction auto-declines. Most devs building on Stripe Issuing have never heard of this. It's called real-time authorization. Every time a card is used, Stripe fires a webhook to your server before the charge is approved. You get the merchant, the amount, the category. You run your logic — is this agent allowed to spend here, is it under the limit — and return approved true or false. Two seconds. Synchronous. If your server is slow, asleep, or returns anything except a 200, the card declines automatically. This is how you build spend controls that actually work — not after the charge posts, but before the money moves. Block specific merchant categories, cap per-transaction amounts, flag unusual spend in real time. Save this. Link in bio for the full webhook implementation guide.