SDK Reference

Full reference for the @senddy/sdk TypeScript package.

Installation#

Terminal

npm install @senddy/sdk
# or
pnpm add @senddy/sdk

Core SDK#

SenddySDK#

The main SDK class for interacting with the Senddy pool contract.

TypeScript

import { SenddySDK } from '@senddy/sdk';

const sdk = new SenddySDK();

Key methods:

Method	Description
`deposit()`	Deposit USDC into the pool
`depositBatch()`	Batch multiple deposits
`depositWithPermit2Sig()`	Deposit using Permit2 signature
`depositWithEIP3009()`	Deposit using EIP-3009 authorization
`quoteDepositShares()`	Get shares for a deposit amount
`quoteWithdrawAssets()`	Get assets for a share amount
`getIndex()`	Get current Merkle tree index
`getNullifierAccumulator()`	Get current nullifier accumulator
`getAssetConfig()`	Get asset configuration
`depositInfo()`	Get deposit details
`generateDepositId()`	Generate a deposit ID

Proof Generation#

proveShield#

Generate a zero-knowledge proof to shield (privatize) a deposit.

TypeScript

import { proveShield } from '@senddy/sdk';

const proof = await proveShield({
  // Shield circuit inputs
});

proveSpend#

Generate a zero-knowledge proof to spend (transfer or withdraw) private notes.

TypeScript

import { proveSpend } from '@senddy/sdk';

const proof = await proveSpend({
  // Spend circuit inputs
});

Attestor Client#

createAttestorClient#

Create a client to communicate with the Senddy attestor service.

TypeScript

import { createAttestorClient } from '@senddy/sdk';

const attestor = createAttestorClient({
  url: process.env.ATTESTOR_URL,
});

// Request a shield attestation
const shieldAttestation = await attestor.attestShield(proof);

// Request a spend attestation
const spendAttestation = await attestor.attestSpend(proof);

Address Utilities#

TypeScript

import {
  isValidSenddyAddress,
  encodeSenddyAddress,
  decodeSenddyAddress,
} from '@senddy/sdk';

// Validate
isValidSenddyAddress('senddy1abc...'); // true/false

// Encode public key to Senddy address
const address = encodeSenddyAddress(publicKeyBytes);

// Decode Senddy address to public key
const { publicKey } = decodeSenddyAddress('senddy1abc...');

Account Abstraction#

Helpers for encoding calldata for smart wallet transactions:

TypeScript

import {
  encodePoolV3DepositWithPermit2Calldata,
  encodePoolV3SpendCalldata,
} from '@senddy/sdk';

// Encode a deposit with Permit2
const depositCalldata = encodePoolV3DepositWithPermit2Calldata({
  amount,
  permit2Signature,
  permitData,
});

// Encode a spend transaction
const spendCalldata = encodePoolV3SpendCalldata({
  proof,
  publicInputs,
});

Sync Engine#

The sync engine monitors the blockchain for new commitments and nullifiers relevant to your keys.

TypeScript

import { SyncEngine, TachyonSyncEngine } from '@senddy/sdk';

// Standard sync
const sync = new SyncEngine({ /* options */ });

// Tachyon sync — O(1) spent detection via precomputed nullifiers
const tachyon = new TachyonSyncEngine({ /* options */ });

Solana Bridge#

TypeScript

import { CCTPBridge } from '@senddy/sdk';

const bridge = new CCTPBridge({
  // CCTP configuration
});

Graph Client#

Query the Senddy subgraph for on-chain data:

TypeScript

import { Subgraph } from '@senddy/sdk';

const graph = new Subgraph();

// Query recent commitments, nullifiers, pool state, etc.

Contract Addresses#

TypeScript

import { SHARED_CONTRACTS, V3_CONTRACTS } from '@senddy/sdk';

// Access deployed contract addresses
console.log(V3_CONTRACTS.pool);     // Pool contract
console.log(V3_CONTRACTS.verifier); // Verifier contract

Key Derivation#

TypeScript

import { deriveKeysWithEIP712 } from '@senddy/sdk';

// Derive Senddy keys from an EIP-712 signature
const keys = await deriveKeysWithEIP712(signer);

Memo Encryption#

TypeScript

import {
  encodeMemoEnvelopeV4_1,
  tryDecryptAsReceiverUnified,
} from '@senddy/sdk';

// Encrypt a memo for a recipient
const envelope = encodeMemoEnvelopeV4_1(memo, recipientPubKey);

// Decrypt a received memo
const memo = tryDecryptAsReceiverUnified(envelope, myPrivateKey);