Quickstart

This walks through the full lifecycle with the core (framework-agnostic) API. For React, see React Hooks.

1. Create a client


import { createCloakClient, LocalStorageNoteStore } from "@privacy-protocol/cloak"
import { createPublicClient, createWalletClient, custom, http } from "viem"
import { sepolia } from "viem/chains"
 
const POOL = "0xYourCloakPool"
const RELAYER = "https://cloak-relayer.onrender.com"
 
const publicClient = createPublicClient({ chain: sepolia, transport: http() })
const walletClient = createWalletClient({ chain: sepolia, transport: custom(window.ethereum) })
 
const cloak = createCloakClient({
  publicClient,
  walletClient,
  chainId: sepolia.id,
  poolAddress: POOL,
  relayerUrl: RELAYER,
  // Persist notes! Notes are the funds. Defaults to in-memory (lost on reload).
  store: new LocalStorageNoteStore(sepolia.id, POOL),
})

2. Deposit

The user signs and pays for the deposit — it is public by design.


import { ETH_ADDRESS } from "@privacy-protocol/cloak"
 
// Deposit 0.1 ETH
const note = await cloak.deposit({ asset: ETH_ADDRESS, amount: 10n ** 17n })
 
// ERC-20: the SDK handles approval automatically
const usdcNote = await cloak.deposit({ asset: "0xToken", amount: 1_000_000n })

The returned note is saved to your store. Let the anonymity set grow before spending.

3. Send a transaction anonymously

send forwards an arbitrary call through an ephemeral proxy, relayed so your address never appears.


import { encodeFunctionData } from "viem"
 
await cloak.send({
  note,
  target: "0xSomeContract",
  data: encodeFunctionData({ abi, functionName: "mint", args: [1n] }),
  value: 5n * 10n ** 16n,        // 0.05 ETH sent with the call
  returnAsset: ETH_ADDRESS,       // capture any ETH the call returns
})

The remaining balance (amount − value − fee) comes back automatically as a new change note in your store.

4. Withdraw privately

To move funds to a fresh address with no visible link to the deposit:


await cloak.withdraw({ note, to: "0xFreshAddress" })       // whole note
await cloak.withdraw({ note, to: "0xFreshAddress", amount: 3n * 10n ** 16n }) // partial

5. Claim returned funds

Funds a call sent back to the proxy become claim notes. Sync, then withdraw them:


await cloak.sync()
for (const claim of await cloak.getClaimables()) {
  await cloak.claim({ claimNote: claim, to: "0xFreshAddress" })
}

6. List spendable notes


await cloak.sync()
const notes = await cloak.getNotes()
const balance = notes.reduce((sum, n) => sum + n.amount, 0n)