FAQ
Short answers to the questions people ask first.
Basics
Is this a mixer?
No. Nothing is pooled and nobody else's funds touch yours. Each payment goes straight from the sender to a new address that belongs only to you.
What is hidden, and what is not?
Hidden: that a stealth address belongs to you, and your total income, as long as you do not link the addresses yourself. Not hidden: who sent a payment, the amount, the time, and every later move from the stealth address. See Trust model.
Does the sender need special software?
A sender who uses an ERC-5564 wallet pays your meta-address directly. With a private name (planned), any wallet that resolves ENS names works: the name resolves to a fresh stealth address.
Does it work with other stealth wallets?
With any wallet that implements ERC-5564: same standard, same Announcer, same registry. Umbra predates the standard and uses its own contracts; our research covers it, but the client does not use it.
Which chains?
The Announcer and the registry sit at the same address on Ethereum, Arbitrum, Base, Optimism and Polygon, so the same keys can receive on all of them.
Keys and safety
Where do my keys come from?
The client asks your wallet to sign one fixed message and derives both keys from the signature, in your browser. The same wallet always gives the same keys.
Can ephemeral see my payments?
Not through the client: your viewing key never leaves your device. If you use a private name (planned), our gateway knows which addresses it issued for your name and the IP of each lookup. Paying your meta-address directly avoids that.
What if I lose my device?
Sign the same message with the same wallet and your keys, payments and balances come back. If you lose the wallet itself, the keys are gone with it, and nobody can restore them.
Does it work with smart-contract wallets?
Only with wallets that produce the same signature every time for the same message. The client checks this before creating keys and stops if your wallet cannot recreate them.
Can I show my income to an accountant?
Yes, by design. Your viewing key gives read-only access to every incoming payment; exporting it from the client is planned. It cannot move funds. Anyone holding it sees all your incoming payments, so share it only with someone you trust with that.
Using it
Do I need ETH in a stealth address to move a token out?
Today, yes: a stealth address pays its own gas. Never fund it from your main wallet. Sponsored, gasless withdrawals are on the roadmap.
Why does the client not let me sweep everything at once?
Because sweeping many stealth addresses into one wallet links them all. In our data, 45.68% of single withdrawals fall into such clusters. See Withdraw without leaking.
Is it legal?
ephemeral is open-source software for receiving payments privately, like a new bank account for each payer. It holds no funds and runs no pool. You can prove a payment or your income with your viewing key. Laws differ by country; this is not legal advice.
The project
Who builds ephemeral?
An independent team led by Sirius, building on Ethereum since 2016. Code, research and numbers are public, so you can judge the work rather than the names.
Is the code open source?
The leak scanner is MIT-licensed and on GitHub. The client is published there as it ships.
Is ephemeral affiliated with the Ethereum Foundation?
No. ephemeral builds on public Ethereum standards and is not affiliated with the Ethereum Foundation or any other project named in these docs.