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

# Prerequisites: Node 18+, pnpm
pnpm install
cd contracts/core && npm install

# Start Hardhat node (terminal 1)
npx hardhat node

# Deploy + setup (terminal 2)
cd contracts/core
npx hardhat run scripts/setup-local.ts --network localhost

# Start API (terminal 3)
pnpm dev:api

# Start checkout (terminal 4)
pnpm dev:checkout

# Start merchant dashboard (terminal 5)
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.