Crypto payment gateway for merchants. Accept USDC, USDT and stablecoins on 5 networks.
Architecture
apps/
checkout/ React + Vite — customer payment page
merchant/ Next.js — merchant dashboard
api/ Fastify — backend API
contracts/
core/ DerampProxy + modules (Hardhat, Solidity ^0.8.28)
packages/
shared/ Shared utilities
assets/
brand/ The logo, and the icons every app is derived from
Networks
| Network | Chain ID | Tokens |
|---|
| Celo | 42220 | USDC, USDT, COPm |
| Arbitrum | 42161 | USDC, USD₮0 |
| Polygon | 137 | USDC, USDT0 |
| Base | 8453 | USDC |
| BSC | 56 | USDC, USDT |
For AI agents
Voulti is agent-usable end to end — the integration API needs no API key:
- MCP server:
claude mcp add voulti -- npx -y voulti-mcp — tools create_invoice, get_invoice, get_payment_link. See mcp/README.md.
- Agent skill:
npx skills add csacanam/voulti — or read it at voulti.com/skill.md.
- Plain HTTP:
POST https://api.voulti.com/invoices with { commerce_id, amount_fiat, reference? } → hosted checkout link. LLM index: voulti.com/llms.txt.
Features
- Self-service registration — merchant connects wallet, names business, done
- Two payment methods — Connect Wallet or Pay by Address (QR + deposit)
- Multi-chain balances — aggregated by token, network auto-selected
- Send funds — withdraw to any wallet from dashboard
- HD wallet sweep — automatic deposit detection and settlement
- Partial/over payment handling — auto-refund on overpay, wait on partial
- i18n — Spanish and English
Smart Contracts
Modular proxy architecture deployed on 5 networks:
- DerampProxy — entry point, routes calls to modules
- DerampStorage — centralized data store
- AccessManager — roles, token/commerce whitelisting
- InvoiceManager — invoice lifecycle
- PaymentProcessor — payment execution, fee calculation
- TreasuryManager — service fee collection
- WithdrawalManager — commerce fund withdrawals
See contracts/core/deployed-addresses/PRODUCTION.md for all addresses.
Operator Wallet
0x21581Cb82D9a66126fBe7639f4AF55DdfEA48E26 — deploys contracts, whitelists commerces, sends gas for HD wallet sweeps.
Local Development
pnpm install
cd contracts/core && npm install
npx hardhat node
cd contracts/core
npx hardhat run scripts/setup-local.ts --network localhost
pnpm dev:api
pnpm dev:checkout
pnpm dev:merchant
API Endpoints
| Method | Path | Auth | Description |
|---|
| POST | /commerces | Privy | Register commerce |
| GET | /commerces/:id | Public | Commerce info |
| GET | /commerces/:id/balances | Privy | Multi-chain balances |
| POST | /invoices | Privy | Create invoice |
| GET | /invoices/:id | Public | Invoice details + tokens |
| POST | /blockchain/create | Public | Create on-chain invoice |
| GET | /blockchain/status/:id | Public | On-chain invoice status |
| POST | /deposit/generate | Public | Generate HD deposit address |
| GET | /deposit/status/:id | Public | Deposit monitoring status |
| GET | /stats | Public | Revenue stats (building in public) |
| GET | /prices/rates | Public | Fiat + token rates from DB |
| POST | /prices/update-fiat-rates | Cron | Update fiat rates (OpenExchangeRates) |
| POST | /prices/update-token-prices | Cron | Update token prices (CoinGecko) |
Cron Jobs
Configure these as scheduled jobs in DigitalOcean (or any scheduler):
| Job | URL | Schedule | Description |
|---|
| Fiat rates | POST /prices/update-fiat-rates | Every hour | Updates USD→COP/EUR/BRL/MXN/ARS rates from OpenExchangeRates |
| Token prices | POST /prices/update-token-prices | Every hour | Updates USDC/USDT/COPm rates from CoinGecko |
| Expire invoices | POST /orders/expire-orders | Every minute | Marks expired invoices as Expired |
| Process emails | POST /notifications/process-emails | Every minute | Sends payment confirmation emails via Resend |
| Process webhooks | POST /notifications/process-url-confirmations | Every minute | Calls commerce confirmation URLs |
Base URL: https://api.voulti.com
Requires env vars: OPENEXCHANGERATE_APPID, COINGECKO_APIKEY, RESEND_APIKEY.
Environment Variables
See .env.example for all required variables.