create-spl-mint.ts

import "dotenv/config";
import {
    Keypair,
    SystemProgram,
    Transaction,
    sendAndConfirmTransaction,
} from "@solana/web3.js";
import { createRpc } from "@lightprotocol/stateless.js";
import { LightTokenProgram } from "@lightprotocol/compressed-token";
import {
    MINT_SIZE,
    TOKEN_PROGRAM_ID,
    createInitializeMint2Instruction,
} from "@solana/spl-token";
import { homedir } from "os";
import { readFileSync } from "fs";

// devnet:
// const RPC_URL = `https://devnet.helius-rpc.com?api-key=${process.env.API_KEY!}`;
// const rpc = createRpc(RPC_URL);
// localnet:
const rpc = createRpc();

const payer = Keypair.fromSecretKey(
    new Uint8Array(
        JSON.parse(readFileSync(`${homedir()}/.config/solana/id.json`, "utf8"))
    )
);

(async function () {
    const mintKeypair = Keypair.generate();
    const decimals = 9;

    // Get rent for mint account
    const rentExemptBalance = await rpc.getMinimumBalanceForRentExemption(
        MINT_SIZE
    );

    // Instruction 1: Create mint account
    const createMintAccountIx = SystemProgram.createAccount({
        fromPubkey: payer.publicKey,
        lamports: rentExemptBalance,
        newAccountPubkey: mintKeypair.publicKey,
        programId: TOKEN_PROGRAM_ID,
        space: MINT_SIZE,
    });

    // Instruction 2: Initialize mint
    const initializeMintIx = createInitializeMint2Instruction(
        mintKeypair.publicKey,
        decimals,
        payer.publicKey, // mint authority
        null, // freeze authority
        TOKEN_PROGRAM_ID
    );

    // Instruction 3: Create SPL interface PDA
    // Holds SPL tokens when wrapped to light-token
    const createSplInterfaceIx = await LightTokenProgram.createSplInterface({
        feePayer: payer.publicKey,
        mint: mintKeypair.publicKey,
        tokenProgramId: TOKEN_PROGRAM_ID,
    });

    const tx = new Transaction().add(
        createMintAccountIx,
        initializeMintIx,
        createSplInterfaceIx
    );

    const signature = await sendAndConfirmTransaction(rpc, tx, [
        payer,
        mintKeypair,
    ]);

    console.log("Mint:", mintKeypair.publicKey.toBase58());
    console.log("Tx:", signature);
})();