Questions

#Using Opacus

#Is it free?

On the testnet, everything uses test money, which is free from Get test funds. Payments inside the pool are free. A deposit costs your wallet about 0.002 SOL of network fees and rent; a cash-out, a swap and a short name have a small fee, shown before you confirm. See The testnet.

#Which wallets work?

Phantom, Solflare and Backpack, and other Solana wallets that can sign messages. On a phone, open the app inside your wallet's own browser.

#Why do I sign twice the first time?

To make sure your wallet signs the same way every time, which is what lets it open the same account again. After the first time on a device, one signature a visit. See Your account.

#Does signing cost anything?

No. A signature is not a transaction: it sends nothing and moves nothing. Sign the Opacus message only on opacus.tech.

#My wallet shows tUSD. What is it?

Opacus's test dollar, made for the testnet. It is worth nothing, and only exists on Solana devnet.

#Can I pay someone who has no Opacus account?

Yes: send them a payment link. They can claim it into a new account, or straight out to any Solana wallet.

#Can a Solana wallet pay my Opacus address?

No. An Opacus address is reached from inside the pool. To bring money in from a wallet, deposit it; to be paid by someone without Opacus, send them a request and they can deposit and pay on the same page.

#How long does a payment take?

A few seconds: the proof on your device, the relayer, Solana. An open Opacus page on the other side sees it within two seconds after that.

#Your money and your privacy

#Can Opacus see my balance?

No. Your balance is worked out inside your own browser from the pool's public list and your keys, which never leave your device. Opacus's services see requests, IP addresses and times, never amounts inside the pool or who pays whom. See What stays private.

#What if I lose my phone or clear my browser?

Open the app with the same wallet on any device and sign: your balance, history and links come back from the pool. What lives only in a browser does not: the people you kept by name, and bills split.

#What if I lose my wallet?

Your wallet is the key to your account. Keep its seed phrase safe: with it you can restore the wallet, and with the wallet, your Opacus account.

#Can someone see that I use Opacus?

A deposit and a cash-out show your wallet moving money into or out of the Opacus pool. Payments inside the pool do not show any wallet of yours.

#Is the testnet audited?

Not yet. See Security and status.