create-mint.ts

import "dotenv/config";
import {
    Keypair,
    ComputeBudgetProgram,
    PublicKey,
    Transaction,
    sendAndConfirmTransaction,
} from "@solana/web3.js";
import {
    createRpc,
    getBatchAddressTreeInfo,
    selectStateTreeInfo,
    CTOKEN_PROGRAM_ID,
} from "@lightprotocol/stateless.js";
import {
    createMintInstruction,
    createTokenMetadata,
} from "@lightprotocol/compressed-token";
import { homedir } from "os";
import { readFileSync } from "fs";

const COMPRESSED_MINT_SEED = Buffer.from("compressed_mint");

function findMintAddress(mintSigner: PublicKey): [PublicKey, number] {
    return PublicKey.findProgramAddressSync(
        [COMPRESSED_MINT_SEED, mintSigner.toBuffer()],
        CTOKEN_PROGRAM_ID
    );
}

// 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 mintSigner = Keypair.generate();
    const addressTreeInfo = getBatchAddressTreeInfo();
    const stateTreeInfo = selectStateTreeInfo(await rpc.getStateTreeInfos());
    const [mintPda] = findMintAddress(mintSigner.publicKey);

    const validityProof = await rpc.getValidityProofV2(
        [],
        [{ address: mintPda.toBytes(), treeInfo: addressTreeInfo }]
    );

    const ix = createMintInstruction(
        mintSigner.publicKey,
        9,
        payer.publicKey,
        null,
        payer.publicKey,
        validityProof,
        addressTreeInfo,
        stateTreeInfo,
        createTokenMetadata(
            "Example Token",
            "EXT",
            "https://example.com/metadata.json"
        )
    );

    const tx = new Transaction().add(
        ComputeBudgetProgram.setComputeUnitLimit({ units: 1_000_000 }),
        ix
    );
    const signature = await sendAndConfirmTransaction(rpc, tx, [
        payer,
        mintSigner,
    ]);

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