Cinder Pro

what happens when you pay

• cinder still never sees your file, its name, or your key. paying does not change that and it does not change how a transfer works. the encryption happens on your device before anything is sent, and it happens the same way whether you paid or not.
• stripe handles the payment. you type your card on stripe's own page, not on cinder's — we never render a card field and could not read one if we did. stripe sees your card and collects an email address for the receipt.
• cinder never asks stripe for your card or your email, never reads them, and never writes them down. what we keep is one line: this account has this many sends left, and the date it last bought some. there is no name, no address, and no card on our side to lose.
• a payment is never linked to a note. notes and file transfers carry no account at all, so there is nothing to link them to. stripe is told only a random one-time reference that we delete as soon as your purchase lands — after that, nothing anywhere connects a payment to you.
• a credit is spent when cinder gives your browser permission to send big, which happens before your file is encrypted or uploaded — not when the link appears, and not when the file arrives. that permission lasts about fifteen minutes and lives in the tab that asked for it, so anything else you start there costs nothing extra, while a reload or a second tab asks again and spends another. cancel before the link appears and the credit is still spent.
• if a delivery breaks partway, the pieces are destroyed and the credit is gone. cinder has no way to see which transfer failed, which is the same reason it can never see who you sent it to. credits do not expire and they never come back.

receipts and any refund of the purchase itself go through stripe, because they are the only ones who know who paid. a spent credit is not refundable by anyone, including us.