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Stripe in Production

Answer the production questions the Stripe API docs do not cover: webhook delivery semantics and idempotency, subscription lifecycle and status transitions, dunning and failed-payment recovery, Checkout and Payment Intent flows with SCA, testing strategy and going live, migrating subscribers between accounts, billing edge cases, and dispute handling — the failure modes that cost money.

45 notes · updated 2026-08-04 · trained 100%

since last sitting: +8 newly passed — this brain is learning

Ask it things like

answers 28/28 on its latest exam
I used Checkout success_url redirect as my fulfillment signal. Customer never gets the email confirmation. What happened?Checkout & Payment Intents✓
My PaymentIntent succeeded client-side in the browser. Can I fulfill the order immediately?Checkout & Payment Intents✓
Subscription renewal fails (bad card). What does Stripe do automatically, and what do I need to implement?Dunning & Failed Payments✓
I'm creating a charge and my code crashes mid-request. When I retry, should I use the same idempotency key?Idempotency & API Calls✓
Should I verify the signature of incoming webhooks, or can I just check the event.id in Stripe?Webhook Delivery & Idempotency✓
Stripe delivers a webhook twice for the same event. How do I know it's a duplicate, and what's the safe way to handle it?Webhook Delivery & Idempotency✓
Never trust the client-side price. What does that mean, and what's the concrete fix?Billing Edge Cases✓
My metered usage-based invoice exploded to $100k when I expected $500. Why?Billing Edge Cases✓

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What it can answer

28 checks
100%
✓Billing Edge Cases5 / 5
✓Checkout & Payment Intents5 / 5
✓Subscription Lifecycle5 / 5
✓Dunning & Failed Payments4 / 4
✓Webhook Delivery & Idempotency4 / 4
✓Testing & Going Live3 / 3
✓Idempotency & API Calls2 / 2
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What is inside

Note titles, so you can judge before you buy. The contents unlock on purchase.

  • Duplicate webhook processing double-billed a customer — what's the recovery runbook? · Webhooks and idempotency
  • Is 'inactive' a real Stripe subscription status? · Subscriptions and lifecycle
  • Upgrade $10 to $50 mid-cycle — why is the invoice $30, not $40? · Subscriptions and lifecycle
  • Can I run a trial without collecting a card upfront? · Subscriptions and lifecycle
  • Crash mid-charge — do I reuse the same idempotency key on retry? · Webhooks and idempotency
  • Renewal fails — what does Stripe do automatically, and what's on me? · Dunning and failed payments
  • Checkout Sessions or the Payment Intents API — which do I build on? · Checkout and Payment Intents
  • PaymentIntent stuck in requires_action — cancel it or keep waiting? · Checkout and Payment Intents

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