Build an onramp
Pix → USDT integration. Quote, conversion, Pix payment, on-chain settlement.
How to build an onramp integration with BlendFi: the end customer pays via Pix, BlendFi settles USDT on-chain to the destination address.
Concepts form the mental model, Operations give per-call detail. Financial mechanics live in Fees, and the runnable walkthrough in Build a PIX → USDT checkout.
Concepts
Overview
Mental model of the onramp in three entities.
Quote
Immutable rate snapshot, valid for 15 minutes.
Conversion
Central onramp entity and its states.
Per-user, per-type lock
One open onramp conversion per end customer.
Operations
Creating a quote
POST /v1/quotes with prerequisites and 15-minute TTL.
Accepting the quote
POST /v1/quotes/:id/accept. Creates the conversion and issues the Pix QR.
Receiving the payment
What happens after the end customer pays the Pix QR.
Cancellation
POST /v1/conversions/:id/cancel, valid only before payment.