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.
“Move sales to another wallet” (/create, JPYC on Polygon only; flag-gated) lets a shop move JPYC from its own wallet to another wallet it controls without holding POL: the shop signs once, OpenPay relays the transfer and pays the gas, and a flat 2 JPYC per transfer is added on top of the amount moved (the destination receives the amount in full; the 1% does not apply).
- 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 is the beginning of the README. Read the rest at the original. Read the full README ↗
