16Design the webhook platform that tells merchants when payments settle. Their endpoint is down. What happens?▼hardStripeRazorpayGitLabunlockedOutbound delivery looks like a queue and a loop until one subscriber hangs for sixty seconds and takes your workers with it. Isolation, retry horizons, and signatures are where the marks are.Open full answer →
18Design notifications for a food delivery app. Order updates cannot be late; coupon blasts cannot spam.▼mediumSwiggyUberLinkedInunlockedTwo contracts in one system: an OTP with a 30-second promise and a sale announcement reaching fifty million phones without burning providers. Priority lanes and double-layer dedup decide the grade.Open full answer →
