Both end in the same place: your own Safe, holding your own USDC. They differ
only in what owns the Safe. Either way the operator relays your signed
orders and pays the gas.
Passkey wallet — no seed phrase, no extension
A passkey wallet is the simplest way to hold your own funds. You approve a prompt with Face ID, Touch ID, or your device PIN, and that’s the whole setup — no browser extension, no app to install, and no seed phrase to write down. There is no private key. Your Safe is owned by a signer contract derived from a WebAuthn credential that lives in your device’s secure hardware. The credential can produce signatures but cannot be exported, and Calibri never holds a key for your account. How it works when you enrol:1
Create the passkey
Your device generates the credential and hands Calibri only the public
half. The private half never leaves your authenticator.
2
Your address is derived immediately
Both the signer contract and your Safe address are computed
deterministically from that public key. Your deposit address exists the
moment you enrol, before anything is on-chain.
3
Nothing is deployed yet
The contracts are only deployed when your first deposit arrives — and
the operator pays for that deployment, not you.
4
Trading
Each order is signed by the passkey and verified on-chain against the signer
contract. To avoid a prompt on every order, unlock a
session key once and orders sign silently
after that — withdrawals and redemptions still require your passkey.
Where your passkey actually lives
This is the part that matters, and it is not the same on every platform. Your passkey is stored by your operating system or password manager, not by Calibri — so whether it syncs, and whether it survives a lost or broken device, is decided by which of these you enrol with.Using your phone to sign on a desktop
Every major desktop browser supports signing with a passkey held on your phone: you scan a QR code, the phone verifies it is physically nearby over Bluetooth, and your phone’s authenticator approves. The passkey never leaves the phone. This is the practical answer on Windows and on any shared or borrowed machine: enrol the passkey on your phone, where it syncs, and use it from the desktop when you need it.Before you fund an account
1
Check your passkey syncs
On iPhone or Android it does by default. On Windows Hello it does not —
enrol through a password manager or on your phone instead.
2
Make sure you can reach the account it syncs to
Your Apple Account, Google Account, or password-manager vault is now what
stands between you and your funds. Make sure it has recovery set up and 2FA
you will not lose.
3
Enrol on a second device if you can
A second passkey on a second device is the cheapest insurance available, and
there is no other kind for a self-custody wallet.
Your own wallet — bring an existing one
If you already use a wallet, connect it and keep signing with what you know. Calibri supports MetaMask, Coinbase Wallet, Rainbow, and any wallet reachable over WalletConnect — including mobile wallets, by scanning a QR code. Here your Safe is owned by your wallet’s address. You approve a signature request in your wallet for each order; the operator relays it and pays the gas, exactly as with a passkey. This path also gives you Sign-In With Ethereum — you can authenticate to Calibri with your wallet instead of an email and password.Which should I choose?
- Never used a crypto wallet? Use a passkey wallet — enrolled on your phone, or on a desktop through a password manager. You get the same on-chain guarantees without installing anything or learning wallet software.
- Already have MetaMask or a mobile wallet? Connect it. You keep your existing signing habits and your existing backup, and you can sign in to Calibri with it too.
- Windows-only, no phone, no password manager? Use your own wallet. A device-bound Windows Hello passkey is a single point of failure for funds nobody can restore.
Adding a second signing key
A passkey wallet starts with one thing that can authorise it. You can add a second — an Ethereum wallet you hold the key for — which makes your funds recoverable if you lose the passkey, and lets your own code trade, withdraw and redeem. It is the same wallet either way: same address, same balance, same positions. But an added key is a full owner — it can withdraw, and it can remove your passkey — so it is worth reading what you are agreeing to before you do it.Signing keys
What a second key can do, how to add and remove one, and what happens if it removes your passkey.
Which signature type your wallet gets
Every order you sign carries asignature_type. It tells the exchange how to
check your signature, and it comes from the wallet you set up — you never pick
it yourself.
Sign up with a passkey and you get a passkey wallet in the same step. Sign up
with an email address and you have no wallet yet — you set one up afterwards in
Settings → Wallet, and that is the moment your type is decided.
Add a second signing key to a passkey wallet and
you stay on type
3. The extra key lets your own code sign orders. Your wallet
is the same wallet.
Read
signature_type from GET /api/v2/atlas/account/wallet before you sign,
rather than hardcoding a number. It is the same field the web app reads.Signing an order
What each type requires of the signature itself, and the exact bytes to sign.
How this compares to email wallets elsewhere
Most prediction markets that let you sign up with an email address do it the same way, and it is worth understanding because it is not what Calibri does. The usual pattern — Polymarket’s, through Magic — is that signing up creates an ordinary wallet with an ordinary private key, generated and held by a third-party key service. It is genuinely your key: the exchange cannot sign with it. But the key exists off your device, and you can export it. Their own API clients depend on exactly that: an email user who wants to trade programmatically exports the private key from the key service and imports it into their bot, then signs withsignature_type=1.
A passkey wallet has no such key to export. Your credential is sealed inside your
authenticator, and the Safe is owned by an on-chain signer contract derived
from its public half — so there is no private key on our servers, in a vendor’s
infrastructure, or anywhere a script can reach. Every signature requires you, in
person, unlocking your device.
Both are called self-custody, and both are: neither operator can move your money.
The difference is what “your key” means. If a key can be exported, then whoever
reaches the account that guards it — by phishing, by an email compromise, or by
legal process against the key service — can reach your funds. A passkey removes
that surface entirely, and the price is the last row of that table.
The difference is who decides. Nobody holds a key on your behalf here; if you want one that a script can use, you add it yourself, knowingly, and you can remove it again. The default stays a wallet with no exportable key at all.
Related
Non-custodial overview
The full self-custody model end to end.
The Safe
What the Safe is and how it is made trade-ready.
Signed orders
How an order is authorised in each model.
Session keys
Trade without a passkey prompt per order.
Funding your account
Getting USDC in.