ZERA Confidential SDK

Unaudited -- This SDK has not yet undergone a formal security audit. See Security for details.

Privacy-preserving transaction infrastructure for Solana. ZERA enables confidential deposits, withdrawals, and shielded transfers using zero-knowledge proofs (Groth16 over BN254) with Poseidon-based commitments.

This monorepo provides the tools third-party developers need to integrate ZERA's privacy features into wallets, dApps, AI agents, and payment systems.

Quick Start

Full Quickstart Guide -- zero to running in under 5 minutes.

1. Point at the Devnet

A hosted Surfpool devnet (1:1 Solana mainnet fork) is available with the ZERA Pool program pre-deployed:

RPC:        http://64.34.82.145:18899
WebSocket:  ws://64.34.82.145:18900

solana config set --url http://64.34.82.145:18899

Or run your own locally with Surfpool.

2. Install the SDK

npm install @zera-labs/sdk @solana/web3.js

3. Try It

import {
  createNote, computeCommitment, computeNullifier,
  hashPubkeyToField, MerkleTree, USDC_MINT,
} from "@zera-labs/sdk";
import { PublicKey } from "@solana/web3.js";
const mint = new PublicKey(USDC_MINT);
const assetHash = await hashPubkeyToField(mint.toBytes());
// Create a private note (1 USDC)
const note = createNote(1_000_000n, assetHash);
const commitment = await computeCommitment(note);
const nullifier = await computeNullifier(note);
console.log("Commitment:", commitment.toString(16));
// Only you know the preimage. The commitment goes on-chain.

4. Run the Demos

# Offline crypto primitives (no network needed)
cd demos/solana-basic && pnpm install && pnpm demo
# Live pool status from devnet
pnpm status
# Full React privacy wallet
cd ../react-demo && pnpm install && pnpm dev

On-Chain Programs

Repository Structure

zera-sdk/
  crates/
    zera-core/         Rust: Poseidon hashing, Merkle tree, note/commitment/nullifier,
                       Groth16 proof formatting, PDA derivation
    zera-neon/         Rust: napi-rs Node.js native bindings for zera-core
  packages/
    sdk/               TypeScript: @zera-labs/sdk — crypto, proofs, tx builders, note store
    mcp-server/        TypeScript: @zera-labs/mcp-server — MCP tool server for AI agents
  demos/
    solana-basic/      CLI demos: offline crypto, deposit flow, pool status reader
    react-demo/        Full React privacy wallet with Solana wallet adapter
  devnet/              Surfpool config for 1:1 mainnet fork (runbooks, program binary, IDL)
  docs/                Architecture, API reference, integration guide, and more

Devnet

The devnet/ directory contains everything needed to run a local 1:1 Solana mainnet fork via Surfpool:

• surfpool.toml -- Network config with Light Protocol programs, state trees, and tokens
• runbooks/ -- Infrastructure-as-code for cloning mainnet state and deploying ZERA Pool
• accounts_dump/ -- Program binary (.so) and IDL (.json)

See devnet/SETUP.md for full details, or use the hosted instance at 64.34.82.145:18899.

Documentation

Key Concepts

• Note: A private UTXO containing an amount, asset identifier, random secret, blinding factor, and memo. Only the creator knows the preimage.
• Commitment: Poseidon(amount, secret, blinding, asset, memo[0..3]) -- a binding, hiding hash stored on-chain as a Merkle leaf.
• Nullifier: Poseidon(secret, commitment) -- revealed when spending a note to prevent double-spend. On-chain existence check via PDA.
• Merkle Tree: Incremental Poseidon-based tree (height 24, capacity 16M leaves) with a 100-entry root history buffer for concurrent transaction tolerance.
• Groth16 Proofs: Four circuits (deposit, withdraw, relayed withdraw, transfer) compiled with Circom, proved with snarkjs, verified on-chain with groth16-solana.

Requirements

• Node.js >= 18
• Solana CLI >= 1.18 (for on-chain interaction)
• Rust >= 1.75 (for building crates)
• Circuit files (.wasm + .zkey) for ZK proof generation (available on request)

Contributing

See CONTRIBUTING.md for development setup, guidelines, and how to submit pull requests.

License

MIT