The payer or payee signs the request which contains the payee, payer, currency, amount, payment details, and arbitrary content data.
The request can be optionally encrypted such that only the payee, payer, and approved 3rd parties can view the request contents.
The request is persisted in IPFS.
The IPFS Content-addressable ID (CID) is stored in a smart contract on Gnosis chain
Requests are created by storing their CIDs on Gnosis, but this doesn't mean payment must occur on Gnosis. Payment can occur on any of the supported chains including 20+ EVM-compatible chains or NEAR.
Update a request
The payee can optionally cancel the request or increase/decrease the expected amount.
The payer can optionally accept the request, indicating that they intend to pay it.
Both payee and payer can add 3rd party stakeholders if the request is encrypted.
Pay a request
The payer derives a paymentReference from the request contents.
The payer calls a function on the payment network smart contract, passing in the token address, to address, amount, and paymentReference.
An event is emitted containing the token address, to address, amount, and paymentReference.
Most requests are "reference-based" meaning that a paymentReference derived from the request contents is logged on-chain via a smart contract that emits an event. Nothing gets written back to IPFS when paying a "reference-based" request.
The exception is when paying a "declarative" request, in which case, data is written back to IPFS. This includes when the payer declares that the payment was sent and the payee declares that the payment was received.
Retrieve a request / Detect a payment
The event is indexed by the payments subgraph
An app can retrieve the request contents from IPFS and calculate the balance based on events from the payments subgraph.
The request balance is calculated by adding up all the on-chain payment events with the same paymentReference. Partial payments are possible.