Documentation
FAQ
Short answers about custody, fees, round-up, signatures and privacy.
Does Spare hold the money?
No. Funds go from the user to the foundation in a normal Stellar payment. Spare never holds funds and takes no cut.
Who pays the fee?
A classic donation is one more payment operation in the same transaction, so the transaction fee is raised by one operation. The Soroban follow-up is its own payment transaction with its own fee. Spare checks the user can cover the donation and the fee before it offers anything.
How does round-up work?
Round-up adds what it takes to reach the next whole dollar, and only when the whole transaction is a Circle-USDC purchase (payments, pathPaymentStrictSend, sell offers). If the amount is already whole, or the real spend is unknown up front, only a fixed amount is offered.
Why does a Soroban call need a second signature?
A Soroban transaction holds only one operation, so the donation cannot ride along. Spare sends a separate payment after the call succeeds, and the confirmation says so before the user accepts.
What do Ledger users see?
The donation is its own payment operation, so the device shows “Payment 0.50 USDC to …” before approval.
Does the dashboard show who donated?
No. The public dashboard aggregates by app and foundation and never lists donor addresses.
How is a foundation verified?
A foundation registers its account in the Spare registry contract and lists the same account in the ACCOUNTS field of its website's stellar.toml (SEP-1). Nobody approves it by hand. “Domain-verified” means exactly that, nothing more.
What if the user says no, or something fails?
Declining signs the original transaction, byte for byte. If a check fails (no trustline, low balance, over your cap, unverified foundation) nothing is offered, and if anything inside Spare errors the original is signed.