orbisend

Orbisend is privacy-enabled stablecoin settlement infrastructure built on Arbitrum, enabling businesses to collect, manage and programmatically disburse stablecoins such as USDC, USDT and USDG without publicly exposing their complete financial activity.

The platform combines payment requests, merchant balances, withdrawals, team controls, wallet operations, transaction management, signed webhooks and programmable disbursements through a unified treasury dashboard and REST API.

Orbisend uses Arbitrum’s low-cost execution environment to provide fast onchain settlement while developing a controlled-visibility layer for commercially sensitive transaction flows. The goal is to give businesses the efficiency and programmability of public blockchain infrastructure without requiring them to broadcast their entire treasury operation.

Key Features

- Private Payments: Peer-to-peer payments settle through a zero-knowledge privacy pool, so the payer and recipient addresses are not linkable on-chain.
- No Wallet Required: Payers and recipients interact through a link, a claim password, and a verification phrase, no wallet connection or account needed.
- Multi-Chain Deposits: Accepts USDT on Arbitrum, USDC on Base (auto-bridged), and USDG on Robinhood Chain, all settling to one pool.
- Merchant Gateway: Merchants can create invoices, run a sandbox/test-deposit flow, and receive webhooks on payment confirmation.
- Relayer-Based Withdrawals: Claims are paid out by a relayer using a client-generated proof, so no direct on-chain link exists between deposit and withdrawal.

Technical Details

- Blockchain: Arbitrum One (chain ID 42161)
- Token: USDT (privacy pool), USDC support in progress
- Smart Contracts: Solidity, entrypoint + privacy pool (zero-knowledge proof based)
- Frontend: Next.js
- Backend: Node.js (Hono), PostgreSQL
- Privacy: Custom zero-knowledge privacy pool (nullifier/commitment scheme), not a third-party SDK
- Cross-chain deposits: Across Protocol (USDC on Base, bridged and swapped to USDT)
- Token Swaps: Uniswap (USDC↔️USDT routing)
- Deployment: Self-hosted VPS (DigitalOcean) behind Caddy, pm2 process manager