OpenPay
OpenPay is a non-custodial QR payment tool that turns JPYC / USDC wallet transfers into a simple checkout for stores, events, creators, and AI agents.
OpenPay は、JPYC / USDC のウォレット送金を、店舗・イベント向け QR 決済体験に変えるノンカストディ型 OSS 決済ツールです。
Demo: https://open-pay.jp · Status: Beta · License: MIT
Live demo (mobile) — receive / register / pay · 実際の操作（受取・レジ・支払い）
Key features
- Non-custodial, no wallet lock-in — payments go directly to the merchant wallet (x402 payments on Arc land in the payee's Circle Gateway balance for withdrawal); OpenPay never holds funds.
Any wallet that signs standard ERC20 / ERC-4337 / EIP-7702 transactions can pay, and no app install is required.
- JPYC / USDC with QR-locked conditions — amount, token, chain, and recipient are pinned per QR; customers cannot mistype them.
- Standard or gasless payment — Standard: the customer pays gas in the native token.
Gasless: the customer pays with just the token. For JPYC, OpenPay sponsors the gas and charges a small per-transaction usage fee, and it works in any wallet.
For USDC, gas is paid in USDC via the paymaster but only for EIP-7702 smart-account wallets — ordinary wallets fall back to standard.
- Receive, register and history — a QR builder (
/create), a mobile-friendly simple register with an itemized cart, a block explorer link on every receipt,
per-browser local history (/history) with accounting-software CSV export, and a printable store kit (/kit).
- Mobile order &
@handle storefronts (live in production) — a store publishes a menu at open-pay.jp/@handle (or shares a /order link); customers browse, add to a cart, and pay by QR.
Order relay to the merchant and kitchen / hall boards are flag-gated layers.
- Tips and permanent
@handle links — a tip widget (link or embed) for creators and a link-in-bio profile that keeps resolving however often the receiver changes; @handle is live on mainnet.
- Notifications, PWA and offline receive QR (live in production) — Web Push when a payment lands, an installable app, and a receive screen whose last QR keeps working with no signal.
- x402 / AI-agent payments (live in production) — a managed JPYC x402 facilitator, a public AI store (
/discovery), and the openpay-x402-mcp MCP package.
Most x402 servers are USDC-only; OpenPay adds JPYC, and its USDC APIs accept Base and Arc.
- OSS, self-hostable under MIT.
Full feature list: docs/FEATURES.md.
日本語の概要: 店舗は、金額・トークン・チェーン・受取先を固定した QR を作るだけで、お客様のウォレットから直接入金を受け取れます（アカウント登録は不要・OpenPay は資金を預かりません）。
JPYC はどのウォレットでもガス代なしで支払えます（USDC のガス代なし決済は EIP-7702 スマートアカウントのウォレットのみで、通常のウォレットは通常決済になります）。
JPYC のガス代なし決済では、お店側に 1 回ごとの OpenPay 利用料がかかります（詳しくは Fees）。
機能の全文は docs/FEATURES.md にあります。
Fees
In gasless mode for JPYC (recover configuration), each payment carries a per-transaction OpenPay usage fee — 1% of the payment with a 2 JPYC minimum (max(2 JPYC, 1%)).
The fee is deducted at settlement and split to the OpenPay fee-receiver atomically in the same transaction.
For payments (/pay, /checkout, the register) the merchant always absorbs the fee and the customer pays exactly the displayed price.
OpenPay never takes custody: the principal price of goods still moves customer→merchant directly on-chain, and only the usage-fee portion is split out.
For tips (/tip, @handle tip pages) the tipper pays a flat gas-equivalent floor (about 2 JPYC) on top of the tip — the 1% does not apply to tips.
There are no OpenPay usage fees on receiving a payment itself, on standard (with-gas) mode outside mobile orders — including the register's standard JPYC path since 2026-10-07
(the customer pays their own gas, OpenPay does not touch it), or on the USDC paths outside mobile orders
(gas is paid by the customer in USDC via the Pimlico / Circle paymaster, or directly on Arc; OpenPay collects 0).
The usage fee applies to JPYC gasless (recover) payments and tips, plus mobile orders described below.
“The shop pays the gas” (register or a fixed-amount payment QR shown on screen, JPYC on Polygon, Kaia or Avalanche; flag-gated) carries no OpenPay usage fee —
the shop’s device pays the gas and, by design, 1 wei is added to the customer’s payment and sent to OpenPay.
- Mobile-order system fee (live in production) — payments made through a mobile-order storefront (
@handle / /order) carry the OpenPay usage fee at a mobile-order rate:
1% for in-store / kiosk (storefront) and 3% for pre-order mobile ordering (preorder), a flat percent (no floor).
On a mobile order only this rate applies (it is not charged in addition to the gasless per-tx usage fee), and it applies on both the gasless relay and standard (with-gas) mode.
A mobile order that an AI agent pays directly over x402 (/api/agent-order/pay) carries the x402 facilitator fee instead of this rate (added by the buyer; the shop receives the order amount in full).
/pay, tips, and ordinary checkout links are unaffected.
- Digital goods store (live in production) — selling digital items on
@handle profiles carries no seller fee; the buyer pays the listed price plus the x402 facilitator fee (1% of price, min 1 JPYC) added on the buyer side.
This pricing is not a percentage skim of arbitrary size: it is a per-transaction service fee for the gas-sponsored JPYC relay, charged at the published rate above (a percentage with a minimum and no upper cap).
OpenPay remains a non-custodial software / infrastructure provider rather than a payment intermediary under the Japanese Payment Services Act framework.
Full details (fee bearer, Arc, register history): docs/FEATURES.md#fees.
Supported tokens and chains
| Token | Merchant receiving chains | Notes |
|---|
| JPYC (v3) | Polygon, Kaia, Avalanche C-Chain | Gasless via OpenPay's self-hosted EIP-3009 relayer (signature-based, no EIP-7702 needed). Ethereum L1 is also supported but standard-mode only, behind a default-off flag. |
| USDC (Circle native — bridged USDC.e is not supported) | Base, Arbitrum, Optimism, Polygon, Ethereum L1, Avalanche C-Chain (standard-mode only for now), Arc (7 with Arc enabled; standard-mode only) | Gasless via the Pimlico ERC20 Paymaster or Circle Paymaster v0.8. USDC gasless requires the buyer's EOA to be an EIP-7702 smart account; ordinary / undelegated wallets fall back to standard payment. |
- USDC balances are chain-specific. Customers can pay from 11 chains via Circle Gateway / CCTP V2 cross-chain, and need the source chain's native gas (ETH/POL etc.) for a cross-chain payment.
NEXT_PUBLIC_NETWORK_ENV=testnet swaps mainnets for the matching testnets.- Per-chain details, the payment-page chain chooser, and the tip widget: docs/FEATURES.md.
Non-custodial design and beta notice
OpenPay never holds merchant funds. Customer payments are sent directly to the merchant wallet (x402 payments through Circle Gateway are credited to the payee's Circle Gateway balance instead, and the payee withdraws them; OpenPay still never holds them). OpenPay does not issue, redeem, custody, or exchange JPYC / USDC.
OpenPay is beta software. Test with small amounts first. Blockchain transactions are irreversible — there is no chargeback.
Always verify recipient address, token, chain, amount, and final receipt.
Merchants should verify actual receipt in their wallet or on a block explorer, even after the completion screen is shown.
OpenPay はベータ版です。まず少額でお試しください。ブロックチェーンの送金は取り消せません（チャージバックはありません）。
送金先・トークン・チェーン・金額を必ず確認し、受け取り側もウォレットやブロックエクスプローラーで入金を確認してください。
Known limitations: docs/FEATURES.md#limitations.
Quick start
For merchants
Just visit https://open-pay.jp, enter your wallet, and generate a QR. No signup.
For developers (self-host)
One-click deploy — spin up your own instance on Vercel:
It boots on testnet by default, and receiving payments works out of the box.
Gasless (Pimlico) and the KV-backed features (SIWE / billing / payment log) need their own keys.
For mainnet, also set NEXT_PUBLIC_NETWORK_ENV=mainnet + NEXT_PUBLIC_FEE_RECEIVER_ADDRESS + per-chain RPC + Sentry.
Self-hosting on Netlify / Railway / any Node host works too.
Or run locally:
git clone https://github.com/cipherwebllc/openpay
cd openpay
npm install
cp .env.local.example .env.local # fill in values
npm run dev # http://localhost:3000
npm run typecheck
npm run lint
npm run test:run
npm run build
npm run e2e:local # Playwright with stub env
For AI agents (x402)
OpenPay includes experimental x402 protocol support for per-request paid API endpoints (AI agent / API use cases — separate from the human checkout flow).
Every USDC-priced API on open-pay.jp answers 402 with two ways to pay the same price: USDC on Base, or USDC on Arc (eip155:5042), live on Arc mainnet since 2026-09-17.
See it without a wallet:
curl -si https://open-pay.jp/api/paid/hello | grep -i '^payment-required:' | cut -d' ' -f2 | base64 -d
# → accepts: [ eip155:8453 (USD Coin), eip155:5042 (GatewayWalletBatched) ] — same amount, same payee
OpenPay also runs a managed JPYC x402 facilitator and a public catalog (/discovery), and offers the Japan Web3 Directory API and the JPYC Shops API.
Third-party catalog listings can also sell in USDC: on Base (relayed to the Coinbase CDP facilitator) and, when the seller also opts in and serves the listing with the no-code x402-jpyc-gateway (the openpay-x402-sdk gate stays Base-only), on Arc through Circle Gateway (buyers pay from a Gateway balance; revenue lands in the seller's Gateway balance). OpenPay takes no fee on the USDC side.
Legal / disclaimer
OpenPay is not a wallet, exchange, custodian, or redemption provider. Users are responsible for complying with applicable laws and regulations in their jurisdiction.
Contact
Want to build OpenPay's payment stack (JPYC/USDC payments, AI-agent payments) into your own service? Reach us on the OpenPay Discord.
OpenPay の仕組み（JPYC・USDC 決済、AI エージェントの支払い）を自社のサービスに組み込みたい方は、OpenPay の Discord からご相談ください。
License
MIT. Self-hosting and forking are fully permitted under MIT. The OpenPay brand and the open-pay.jp domain belong to the operator and are not part of the license grant.
Changelog: CHANGELOG.md · Operator deploy guide: docs/DEPLOY_CHECKLIST.md
