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
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
License
MIT
