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Deposit

TL;DR

A deposit is an on-chain transaction that moves SPL tokens into the vault and mints a private note for you, a commitment added to the Merkle tree. You sign it with your wallet, not your trading key, and the deposit never touches the matching engine. Record the resulting note locally: deposit notes are the one thing you must back up yourself.

What a deposit does​

Depositing transfers tokens from your SPL token account into the vault program and appends a note commitment to the on-chain tree. From that point your balance is the note, not a ledger entry: the amount, owner, and token are sealed inside the commitment, and only your keys can recognize and spend it (see Account Model).

A deposit is a direct on-chain action. It is not an API call to the engine, and it does not require a bearer token. The engine only ever sees the note later, as committed collateral when you place an order.

Using the SDK​

import { getDepositFunction } from "@darknyx/sdk";

const deposit = getDepositFunction({ client });

const receipt = await deposit({
  tokenMint,                    // 32-byte mint of the asset
  amount: 100_000_000n,         // base units
  depositorTokenAccount,        // your SPL token account for that mint
});
// receipt carries the new note's commitment and its Merkle leaf index.

The SDK builds the note opening, sends the on-chain deposit transaction, and reads the new leaf back from the deposit event so the note is immediately spendable.

Record your deposit notes​

Deposit notes are not seed-recoverable

A deposit note's secret opening comes from a per-deposit counter you own, not from a chain-readable ciphertext. That means a deposit note cannot be reconstructed from your seed alone on a fresh device. Store each deposit note in your local note store (the SDK exposes depositNoteFromReceipt for this) and keep that store backed up.

This is the one exception to "recover everything from your seed." Trade change notes are recoverable from on-chain data (see Fills Channel), but the original deposits are not.

After depositing​

The new note is spendable. You can:

  • back an order with it (see Place Order),
  • merge it with other notes to form a larger one, or
  • withdraw it back to an SPL token account.
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