DevelopersAPI Reference
Getting started

Introduction

Welcome to the Eurosia Systems API. Build crypto-to-fiat payment flows, wallet custody, KYC/AML compliance, and real-time settlement into your product using our REST API. All requests use JSON over HTTPS.

Terminology

TermExplanation
PartnerYou — the platform integrating Eurosia Systems infrastructure.
UserAn end-user of your platform who holds a custody wallet.
WalletMPC-secured custody account holding crypto via Fireblocks.
Payment sessionA single crypto→fiat payment intent at POS or QR scan.
SwapReal-time conversion of crypto to EUR/USD at locked spot rate.
SettlementDaily consolidated payout to your registered IBAN.
KYCIdentity verification required before live payment sessions.
MCCMerchant Category Code — used to block high-risk categories.

Base URLs

sandboxhttps://api-sandbox.eurosiasystems.com/v1
livehttps://api.eurosiasystems.com/v1

HTTP response codes

CodeMeaningDescription
200OKRequest succeeded.
201CreatedResource created successfully.
400Bad requestMissing or invalid parameters.
401UnauthorizedInvalid or missing API key.
404Not foundResource does not exist.
409ConflictConcurrent request — retry after brief delay.
422UnprocessableSwap failure, KYC reject, or compliance block.
429Rate limitedToo many requests — see rate limits.
50xServer errorTemporary issue on our end.