System Overview

Stableyard’s architecture is designed as a programmable middleware layer that connects applications to blockchain networks through unified payment primitives.
LayerComponents
ApplicationsWallets, dApps, Merchants, PSPs, Enterprises
SDK / APIREST API, TypeScript SDK, Webhooks
Stableyard CoreMoney Account, Routing, Settlement, Policy Engine
ExecutionIntent Engine (x402+), Solver Network, PSP Integration
NetworksEthereum, Base, Arbitrum, Polygon, Movement, Solana

Payment Flow

Core Components

Intent Engine (x402+)

The x402+ execution layer powers all payment flows:
Flow TypeDescription
Scan-and-PayQR code payments at merchants
Payment LinksShareable payment requests
Off-ramp SettlementStablecoin to fiat conversion
Merchant PayoutsAutomatic settlement to merchants
Developer PayoutsAPI-triggered disbursements
P2P TransfersWallet to wallet payments
Agent BankingProgrammable B2B flows

Intent Structure

Every intent contains:
FieldPurpose
PayerSource Money Account or address
ReceiverDestination Money Account or address
AssetToken being transferred
ChainSource and destination networks
Settlement PathHow funds should be delivered
MetadataOrder ID, memo, custom fields

Settlement & Routing Layer

The Stableyard network handles:
  • Intent Routing — Cross-chain path finding
  • Liquidity Execution — Solver-based fulfillment
  • PSP Settlement — Fiat delivery via partners
  • Asset Normalization — User pays USDC, merchant receives fiat
  • Rebalancing — Automated liquidity management

Security Architecture

LayerSecurity Features
Vault LayerSafe-based multisig, non-custodial design
Policy LayerOn-chain spend limits, role-based access
Execution LayerVerified settlement, replay protection
Compliance LayerKYC/AML hooks, audit trails

Integration Patterns

For Merchants

  1. Create Money Account via API
  2. Generate payment links or QR codes
  3. Receive webhook on payment completion
  4. Funds settle to preferred currency

For PSPs

  1. White-label Money Account infrastructure
  2. Map existing merchant IDs to accounts
  3. Integrate settlement callbacks
  4. Enable stablecoin acceptance without hardware changes

For Developers

  1. Register users with Money Account API
  2. Deploy vaults programmatically
  3. Create payment intents via API
  4. Handle webhooks for status updates
Next: Learn about Identity — human-readable payment handles.