Light protocol

Light Protocol Development Guide

Build scalable, cost-efficient applications on Solana with Light Protocol - the infrastructure platform enabling rent-free tokens and accounts with L1 performance and security.

Overview

Light Protocol provides two complementary technologies:

• ZK Compression: Create rent-free compressed tokens and PDAs using zero-knowledge proofs. Uses Merkle trees and validity proofs to store state efficiently.
• Light Token Program: A high-performance token standard that reduces mint and token account costs by 200x compared to SPL tokens.

Key Benefits

Benefit	Description
200x Cost Reduction	Compressed token accounts cost ~5,000 lamports vs ~2,000,000 for SPL
Rent-Free Accounts	No upfront rent-exemption required for tokens or PDAs
L1 Security	All execution and state remains on Solana mainnet
Full Composability	Works with existing Solana programs and wallets (Phantom, Backpack)

Program IDs

Program	Address	Description
Light System Program	SySTEM1eSU2p4BGQfQpimFEWWSC1XDFeun3Nqzz3rT7	Core system program
Light Token Program	cTokenmWW8bLPjZEBAUgYy3zKxQZW6VKi7bqNFEVv3m	Compressed token operations
Account Compression	compr6CUsB5m2jS4Y3831ztGSTnDpnKJTKS95d64XVq	Account compression program

Quick Start

Installation

# Install TypeScript SDKs
npm install @lightprotocol/stateless.js @lightprotocol/compressed-token

# Install CLI for local development
npm install -g @lightprotocol/zk-compression-cli

RPC Setup

Light Protocol requires a ZK Compression-enabled RPC. Use Helius:

import { Rpc, createRpc } from "@lightprotocol/stateless.js";

// Mainnet
const rpc = createRpc(
  "https://mainnet.helius-rpc.com?api-key=<YOUR_API_KEY>",
  "https://mainnet.helius-rpc.com?api-key=<YOUR_API_KEY>"
);

// Devnet
const devnetRpc = createRpc(
  "https://devnet.helius-rpc.com?api-key=<YOUR_API_KEY>",
  "https://devnet.helius-rpc.com?api-key=<YOUR_API_KEY>"
);

Basic Setup

import { Rpc, createRpc } from "@lightprotocol/stateless.js";
import {
  createMint,
  mintTo,
  transfer,
} from "@lightprotocol/compressed-token";
import { Keypair, PublicKey } from "@solana/web3.js";

// Initialize RPC connection
const rpc = createRpc(process.env.RPC_ENDPOINT!, process.env.RPC_ENDPOINT!);

// Load wallet
const payer = Keypair.fromSecretKey(
  Uint8Array.from(JSON.parse(process.env.PRIVATE_KEY!))
);

console.log("Connected to Light Protocol");
console.log("Wallet:", payer.publicKey.toBase58());

---

ZK Compression

ZK Compression enables rent-free compressed tokens using zero-knowledge proofs. Compressed accounts are stored in Merkle trees and verified using validity proofs.

Create Compressed Token Mint

import { createMint } from "@lightprotocol/compressed-token";
import { Keypair } from "@solana/web3.js";

const payer = Keypair.generate();
const mintAuthority = payer;

// Create mint with token pool for compression
const { mint, transactionSignature } = await createMint(
  rpc,
  payer,           // Fee payer
  mintAuthority.publicKey,  // Mint authority
  9,               // Decimals
);

console.log("Mint created:", mint.toBase58());
console.log("Transaction:", transactionSignature);

Mint Compressed Tokens

import { mintTo } from "@lightprotocol/compressed-token";

const recipient = new PublicKey("...");
const amount = 1_000_000_000; // 1 token with 9 decimals

const transactionSignature = await mintTo(
  rpc,
  payer,           // Fee payer
  mint,            // Mint with token pool
  recipient,       // Recipient address
  mintAuthority,   // Mint authority (signer)
  amount,          // Amount to mint
);

console.log("Minted:", transactionSignature);

Mint to Multiple Recipients

const recipients = [
  new PublicKey("recipient1..."),
  new PublicKey("recipient2..."),
  new PublicKey("recipient3..."),
];

const amounts = [
  1_000_000_000,
  2_000_000_000,
  3_000_000_000,
];

const transactionSignature = await mintTo(
  rpc,
  payer,
  mint,
  recipients,      // Array of recipients
  mintAuthority,
  amounts,         // Array of amounts (must match recipients length)
);

Transfer Compressed Tokens

import { transfer } from "@lightprotocol/compressed-token";

const recipient = new PublicKey("...");
const amount = 500_000_000; // 0.5 tokens

const transactionSignature = await transfer(
  rpc,
  payer,           // Fee payer
  mint,            // Mint with token pool
  amount,          // Amount to transfer
  sender,          // Token owner (signer)
  recipient,       // Destination address
);

console.log("Transferred:", transactionSignature);

Note: Compressed token transfers use a consume-and-create model. Input accounts are consumed and new output accounts are created with updated balances.

Compress SPL Tokens

Convert existing SPL tokens to compressed format:

import { compress, compressSplTokenAccount } from "@lightprotocol/compressed-token";

// Compress specific amount to a recipient
const transactionSignature = await compress(
  rpc,
  payer,
  mint,
  amount,
  owner,           // SPL token owner
  recipient,       // Compressed token recipient
  tokenAccount,    // Source SPL token account
);

// Compress entire SPL token account (reclaim rent)
const tx = await compressSplTokenAccount(
  rpc,
  payer,
  mint,
  owner,
  tokenAccount,
  // Optional: amount to keep in SPL format
);

Decompress to SPL Tokens

Convert compressed tokens back to SPL format:

import { decompress } from "@lightprotocol/compressed-token";

const transactionSignature = await decompress(
  rpc,
  payer,
  mint,
  amount,
  owner,           // Compressed token owner (signer)
  recipient,       // SPL token recipient
);

Query Compressed Accounts

// Get all compressed token accounts for an owner
const tokenAccounts = await rpc.getCompressedTokenAccountsByOwner(
  owner.publicKey,
  { mint }
);

console.log("Token accounts:", tokenAccounts.items.length);

// Calculate total balance
const totalBalance = tokenAccounts.items.reduce(
  (sum, account) => sum + BigInt(account.parsed.amount),
  BigInt(0)
);
console.log("Total balance:", totalBalance.toString());

// Get compressed account balance
const balance = await rpc.getCompressedTokenAccountBalance(accountHash);

// Get validity proof for transaction
const proof = await rpc.getValidityProof(compressedAccountHashes);

Create Token Pool for Existing Mint

Add compression support to an existing SPL mint:

import { createTokenPool } from "@lightprotocol/compressed-token";

// Add token pool to existing SPL mint
// Note: Does NOT require mint authority
const transactionSignature = await createTokenPool(
  rpc,
  payer,           // Fee payer
  existingMint,    // Existing SPL mint
);

---

Light Token Program

The Light Token Program is a separate high-performance token standard that reduces costs without ZK proofs. It's optimized for hot paths and provides wrap/unwrap interoperability with SPL tokens.

Key Differences from ZK Compression

Feature	ZK Compression	Light Token Program
Technology	Zero-knowledge proofs	Optimized token standard
Use Case	Compressed tokens/PDAs	High-performance tokens
Compute Units	Higher (proof verification)	Lower (optimized hot paths)
Interop	Compress/decompress SPL	Wrap/unwrap SPL & Token-2022

Create Light Token Mint

import { createLightMint } from "@lightprotocol/light-token";

const { mint, transactionSignature } = await createLightMint(
  rpc,
  payer,
  mintAuthority.publicKey,
  9,  // decimals
);

console.log("Light mint created:", mint.toBase58());

Mint to Light-ATA

import { mintToLightAta } from "@lightprotocol/light-token";

const transactionSignature = await mintToLightAta(
  rpc,
  payer,
  mint,
  recipient,
  mintAuthority,
  amount,
);

Wrap SPL to Light Token

import { wrapSpl } from "@lightprotocol/light-token";

// Wrap SPL tokens to Light tokens
const transactionSignature = await wrapSpl(
  rpc,
  payer,
  mint,
  amount,
  owner,
  splTokenAccount,
);

Unwrap Light Token to SPL

import { unwrapToSpl } from "@lightprotocol/light-token";

// Unwrap Light tokens back to SPL
const transactionSignature = await unwrapToSpl(
  rpc,
  payer,
  mint,
  amount,
  owner,
  recipient,  // SPL token account
);

---

JSON RPC Methods

Light Protocol provides 21 specialized RPC methods for compressed accounts. Key methods:

Method	Description
getCompressedAccount	Get compressed account by address or hash
getCompressedAccountsByOwner	Get all compressed accounts for an owner
getCompressedTokenAccountsByOwner	Get compressed token accounts for an owner
getCompressedTokenAccountBalance	Get balance for a token account
getCompressedTokenBalancesByOwner	Get all token balances for an owner
getCompressedMintTokenHolders	Get all holders of a compressed mint
getValidityProof	Get ZK proof for compressed accounts
getMultipleCompressedAccounts	Batch fetch compressed accounts
getTransactionWithCompressionInfo	Get transaction with parsed compression data
getIndexerHealth	Check indexer status

See resources/json-rpc-methods.md for complete documentation.

---

Best Practices

Transaction Limits

• 4 compressed accounts per transaction: Split large operations into multiple transactions
• Compute unit budget: Add extra compute units for proof verification

import { ComputeBudgetProgram } from "@solana/web3.js";

// Add compute budget for complex transactions
const modifyComputeUnits = ComputeBudgetProgram.setComputeUnitLimit({
  units: 300_000,
});

Batch Operations

// Process multiple recipients in batches
async function batchMint(
  recipients: PublicKey[],
  amounts: number[],
  batchSize = 4
) {
  const results = [];

  for (let i = 0; i < recipients.length; i += batchSize) {
    const batchRecipients = recipients.slice(i, i + batchSize);
    const batchAmounts = amounts.slice(i, i + batchSize);

    const sig = await mintTo(
      rpc,
      payer,
      mint,
      batchRecipients,
      mintAuthority,
      batchAmounts,
    );

    results.push(sig);
  }

  return results;
}

Error Handling

try {
  const signature = await transfer(rpc, payer, mint, amount, sender, recipient);
  console.log("Success:", signature);
} catch (error) {
  if (error.message.includes("TokenPool not found")) {
    // Create token pool first
    await createTokenPool(rpc, payer, mint);
  } else if (error.message.includes("Insufficient balance")) {
    // Check balance before transfer
    const accounts = await rpc.getCompressedTokenAccountsByOwner(sender.publicKey, { mint });
    console.log("Available balance:", accounts.items);
  } else {
    throw error;
  }
}

Delegation

import { approve, transferDelegated } from "@lightprotocol/compressed-token";

// Approve delegate
const approveSig = await approve(
  rpc,
  payer,
  mint,
  amount,
  owner,           // Token owner
  delegate,        // Delegate public key
);

// Transfer as delegate
const transferSig = await transferDelegated(
  rpc,
  payer,
  mint,
  amount,
  delegate,        // Delegate (signer)
  recipient,
);

---

Resources

Official Documentation

• ZK Compression Docs
• Light Protocol Whitepaper

GitHub Repositories

• Light Protocol - Main repository
• Example Node.js Client
• Example Web Client

Community

• Discord - Light Protocol Discord
• Helius Discord - RPC provider support

Wallet Support

• Phantom - Native compressed token support
• Backpack - Native compressed token support

---

Skill Structure

light-protocol/
├── SKILL.md                    # This file
├── resources/
│   ├── program-addresses.md    # Program IDs, state trees, RPC endpoints
│   ├── json-rpc-methods.md     # All 21 RPC methods documented
│   ├── sdk-reference.md        # TypeScript SDK reference
│   └── github-repos.md         # Official repositories
├── examples/
│   ├── setup/
│   │   └── example.ts          # Basic setup
│   ├── zk-compression/
│   │   ├── create-mint.ts      # Create compressed mint
│   │   ├── mint-tokens.ts      # Mint compressed tokens
│   │   ├── transfer-tokens.ts  # Transfer compressed tokens
│   │   ├── compress-spl.ts     # Compress SPL tokens
│   │   └── decompress.ts       # Decompress to SPL
│   ├── light-token-program/
│   │   ├── create-light-mint.ts
│   │   ├── mint-light-tokens.ts
│   │   └── wrap-unwrap.ts
│   ├── querying/
│   │   └── fetch-accounts.ts   # Query compressed accounts
│   └── advanced/
│       ├── batch-operations.ts # Multi-recipient operations
│       └── delegation.ts       # Approve and delegate transfers
├── templates/
│   └── setup.ts                # Complete starter template
└── docs/
    └── troubleshooting.md      # Common issues and solutions