

Monnify Build Sessions 02: Webhooks and Idempotency in Production
Monnify Build Sessions is a monthly workshop for developers building payment integrations.
Each session tackles a real decision or problem developers run into when integrating payments, not just "how to write the code," but how to get the underlying choices right.
Session 02: Webhooks and Idempotency in Production
A webhook arrives twice. Or it doesn't arrive at all. Both look exactly like "everything's fine" until reconciliation tells you otherwise , and by then, a duplicate credit or a missed confirmation is already expensive to unwind. This session walks through how to build a webhook handler that actually survives production: verifying deliveries, deduping retries, and knowing what to do when nothing arrives at all, using Monnify as the working example throughout, with a live build, not just slides.
What you'll walk away with:
A working pattern for idempotent webhook handling you can drop into your own code
A look at what actually breaks (duplicate credits from retries, missed webhooks, out-of-order delivery) and what it costs when it's caught late
A quick-reference flow for verifying, deduping, and processing safely
Open to all developers, whether you're already building on Monnify or still evaluating a provider.