Depositing

Deposits move funds from your public wallet balance into the Nullmask shielded pool.

Steps

1. Navigate to the Shield screen

2. Select the token (ETH or ERC-20)

3. Enter the amount

4. If your wallet is on the wrong network, you'll be prompted to switch to the base chain (e.g., Ethereum Mainnet)

5. For ERC-20 tokens, approve the token allowance if needed

6. Confirm the deposit transaction in your wallet

What Happens

1. Your wallet sends a deposit() transaction to the Nullmask contract on the base chain

2. The transaction includes the deposit amount plus a small gas escrow (to cover the guard's gas costs)

3. The deposit enters a pending state

4. The guard service screens your address

5. Once approved, a note is created in the Merkle tree representing your shielded balance

6. The deposit appears in your shielded balance (typically within 15-30 seconds)

Deposit Statuses

Status	Description
Pending	Awaiting guard review
Approved	Note added to Merkle tree
Rejected	Funds refunded to depositor
Reverted	Depositor withdrew pending deposit

ERC-20 Deposits

For ERC-20 tokens:

1. The app checks if the contract has sufficient allowance

2. If not, you'll be prompted to approve the token

3. The deposit transfers tokens via safeTransferFrom

4. Fee-on-transfer tokens are supported — the actual deposited amount is measured via balance delta

Gas Escrow

Each deposit includes a small ETH gas escrow sent alongside the deposit. This escrow:

• Pays the guard's gas costs for approving or rejecting the deposit

• Is paid to the guard regardless of the outcome

• Is refunded if you withdraw a pending deposit

Withdrawing a Pending Deposit

If your deposit is still pending (not yet approved or rejected), you can withdraw it:

• Call withdrawPendingDeposit() on the contract

• Both the deposit amount and gas escrow are refunded