02 · Custody
Wallet and
custody
Crumble never holds your keys, and it has no standing permission to move your money.
What you sign
Every round-up is a transaction you approve yourself, at the moment it happens. There is no subscription to a keeper, no session key, and nothing that keeps working while you are asleep.
Paying with an ERC-20 such as USDG takes the usual two steps: an approve for the amount, then the swap. You choose the allowance in your wallet, and you can revoke it there at any time. Paying with native ETH skips the approval entirely — the amount rides along with the transaction.
Where your stocks live
Bought Stock Tokens are held by the vault contract and recorded against your address. They are not pooled, not lent out, not staked and not rehypothecated. The contract does one thing with them: give them back when you ask.
Two views let you check the balance yourself without trusting the interface: balanceOf(you, token) for a single holding and holdings(you) for the lot.
Taking it back
withdraw(token, amount, to)— any token you hold here, any amount, to any address you name.withdrawAll(to)— everything in one transaction.
Neither call can be paused, gated, delayed or refused. There is no lockup, no notice period, no minimum balance and no withdrawal fee. If our website disappears tomorrow, the contract is still there and both calls still work from any block explorer.
No pause switch exists. Not one the owner is promising not to use — there is no such function in the contract to call. The same applies to withdrawals: nothing in the code can stand between you and your balance.
What the vault cannot do
It can
- Move the exact amount you sent with your transaction
- Buy the Stock Tokens in the basket you set
- Send your withdrawal where you tell it
It cannot
- Pull anything from your wallet on its own
- Touch a token you did not hand it
- Move a balance recorded against you to anyone else
- Stop you withdrawing, for any reason
A note on approvals
Granting an unlimited allowance is convenient and common, and it is still a standing permission — one that outlives your session and any particular version of our front end. Approving only what you are about to spend is the more careful habit, with any contract, not just this one.