PayLoop

Non-custodial USDC subscriptions on Stellar. A subscriber signs one policy (merchant, amount, interval, and a cap on the total) from their own wallet. The first charge settles in the same transaction; a relayer submits each later charge when it is due. Funds stay in the subscriber's wallet until then, and the subscriber can pause, resume, or revoke at any time.

Path	What it is
contract/	The Soroban contract (Rust, soroban-sdk 29), its tests, deployment manifests, and security review
sdk/	@web-soroban/payloop: build, sign, and track policies from any wallet
examples/merchant/	An Express server that unlocks content for active subscribers

Deployments

Network	Contract	Token
Testnet	CCNMZWP2NQMTJF2J42W4DNYNOAQQYWOCJ2IQROXWYSJVOI3DKSH7YRIH	Circle test USDC
Mainnet	CDQ6I65CP3JHLNGMEHWE4BP2OMLWOUMZ77U53JPAURFZPZBVH6PYEXPN	Circle USDC

Both run the same build (wasm d42be154c35ac597792f41d83ccf1d70abd29edebdec135a44ce31fd78a19318).

Mainnet status: the contract has had an internal security review, and every finding is fixed or documented in contract/AUDIT.md. It has not been independently audited. Start with small amounts.

How it works

Call	Signer	Effect
create_policy	subscriber	Grants the USDC allowance and takes the first charge. Any failure reverts everything.
charge	anyone	Takes a charge once it is due. Recipient, amount, schedule, and cap are fixed by the policy.
pause / resume	subscriber	Stops and restarts charges. Missed periods are never back-billed.
revoke	subscriber	Ends the policy. Final.
cancel	merchant	Ends the policy from the merchant side. Final.
refresh_allowance	subscriber	Renews or trims the allowance to what live policies may still charge.

The contract never holds funds, has no admin, and cannot be upgraded. WebSoroban runs the relayer and an indexer, so a merchant runs no chain infrastructure.

Use it

Subscribe from a browser wallet:

npm install @web-soroban/payloop @stellar/stellar-sdk

import { createPayLoopClient } from '@web-soroban/payloop'

const payloop = createPayLoopClient({ network: 'mainnet', rpcUrl: 'https://your-mainnet-rpc' })

await payloop.send(
  () => payloop.buildCreatePolicy({
    subscriber, merchant, amount: '9.99', intervalSeconds: 30 * 86_400, cap: '119.88',
  }),
  (xdr) => signWithWallet(xdr),
)

Gate access on a server:

const plan = await payloop.activeSubscription({
  subscriber, merchant, amount: '9.99', intervalSeconds: 30 * 86_400,
})

Or try it without code at payloop.websoroban.in.

Develop

cd contract && cargo test && stellar contract build   # stellar-cli 25.2+
cd sdk && npm install && npm test

To check a deployment, run shasum -a 256 target/wasm32v1-none/release/payloop.wasm in contract/ and compare the result with deployments/<network>.json.

Learn more

• PayLoop guide
• One-off paid requests: WebSoroban/x402-kit

License

MIT