SolanaにおけるマネーマーケットファンドのNAVストライク

NAV（純資産価値）ストライクとは、取引日中にファンドの口数が価格付けされ、注文が執行される決まった時間のことです。従来のファンドは通常、市場終了時に1日1回のストライクを行いますが、Solanaの速度と低コストにより、1日中に複数回のストライクが可能となり、投資家に柔軟性をもたらします。

NAVとは何か？

ファンドとは、多くの投資家が共同で保有する資産のプールです。**NAV（純資産価値）**は、ファンドの1口あたりの価格を示します。次のように考えてください：

NAV = (Total Value of Everything in the Fund - liabilities) ÷ Number of Shares

例えば、あるファンドが1,000万ドルの資産を保有し、1,000万口の発行済み口数がある場合、1口あたりの価値は1.00ドルになります。

NAVが重要な理由は何か？

口数の購入（申込み）：現在のNAVで支払います。NAVが1.02ドルの場合、102ドルを投資すると100口を取得できます。
口数の売却（換金）：現在のNAVを受け取ります。NAV 1.02ドルで100口を換金すると、102ドルを受け取れます。

マネーマーケットファンドは通常、獲得した利息に基づく小幅な変動を伴いながら、1.00ドル前後の安定したNAVを維持します。

課題

マネーマーケットファンドへの投資では、従来、異なるタイミングで次の2つのことが発生します：

注文を提出する → 市場終了まで待機する
NAV算出 → T+1またはT+2で口数の発行・換金

これにより、いくつかの問題が生じます：

執行の遅延：午前中に提出された注文は午後4時まで待機
決済の遅延：資金が1〜2日間宙に浮いた状態になる
柔軟性の欠如：1日1回しか取引できない
価格の陳腐化：注文から執行までの間にNAVが古くなる可能性がある

解決策

SolanaのNAVストライクは、アトミック実行による複数の日次決済ウィンドウを実現します。注文はキューに入り、各ストライク時刻に現在のNAVで即時執行されます。

┌─────────────────────────────────────────────────────────────┐
│              MULTIPLE DAILY NAV STRIKES                     │
├─────────────────────────────────────────────────────────────┤
│                                                             │
│   9:30 AM     12:00 PM     2:30 PM      4:00 PM            │
│      │           │            │            │                │
│      ▼           ▼            ▼            ▼                │
│   ┌─────┐    ┌─────┐     ┌─────┐      ┌─────┐              │
│   │STRIKE│   │STRIKE│    │STRIKE│     │STRIKE│             │
│   │NAV=$1│   │NAV=$1│    │NAV=$1│     │NAV=$1│             │
│   │.0012 │   │.0015 │    │.0018 │     │.0020 │             │
│   └─────┘    └─────┘     └─────┘      └─────┘              │
│       │          │           │            │                 │
│       ▼          ▼           ▼            ▼                 │
│   Process    Process     Process      Process               │
│   Orders     Orders      Orders       Orders                │
│                                                             │
│   ✅ Atomic settlement at each strike                       │
│   ✅ NAV stored onchain in token metadata                  │
│   ✅ Less stale prices                │
│                                                             │
└─────────────────────────────────────────────────────────────┘

このガイドでは、SPL Token 2022拡張機能を使用してSolana上でNAVストライクを実装する方法を紹介します。コンプライアンスに準拠したファンド口数の発行にはToken Extensions Programを、決済には標準的なUSDCを使用し、カスタムRustプログラムを記述することなく実現します。

教育目的の参照実装

この実装のソースコードを使用して、NAVストライクをローカルで試すことができます。

このガイドは、探索および教育目的のみの参照実装を提供します。以下を行わずにこのコードを本番環境で直接使用しないでください：

包括的なセキュリティ監査
適切な鍵管理システム
法令遵守レビュー
法的相談
徹底的なテストと修正

アーキテクチャ概要

NAVストライクシステムは、以下のコアコンポーネントで構成されています：

ファンド口数トークン：NAVをオンチェーンに保存するメタデータを持つSPL Token 2022
決済通貨：標準USDC（既存のSPLトークン）
ファンド管理者：委任された権限を通じてストライクを調整
ホワイトリストシステム：ファンド口数を保有できるアドレスを制御

主要な設計原則

カスタムプログラム不要：Token Extensions Programと標準USDCのみを使用
アトミック決済：単一トランザクションにより、申込み・換金が完了するかまたは一緒に失敗することを保証
デフォルトフリーズ状態：法令遵守のため、口数の保有には明示的なホワイトリスト登録が必要
委任権限：ファンド管理者は資産を預かることなく運営
オンチェーンNAV：現在の価格がトークンメタデータに保存され、公開で検証可能

ステージ1：ファンドのセットアップ

メタデータ拡張機能付きのファンド口数トークンを作成
NAVを1.00ドルで初期化
日次ストライクスケジュールを設定
機関投資家をホワイトリストに登録

ステージ2：ストライク前の期間

投資家が申込み・換金リクエストを提出
注文が次のストライク時刻のためにキューに入る
ファンドが暫定NAVを算出
リスクチェックを実施

ステージ3：NAVストライクの執行

At Strike Time (e.g., 14:30):
├── Calculate final NAV from underlying assets
├── Update onchain NAV in metadata
├── Process all pending subscriptions atomically
│   └── USDC → Fund Shares at exact NAV
├── Process all pending redemptions atomically
│   └── Fund Shares → USDC at exact NAV
└── Emit strike completion event

✅ STRIKE COMPLETE (all trades at same NAV)

ステージ4：ストライク後

取引確認書を生成
ファンドの構成を更新
次のストライクに向けて準備
カストディアンと照合

委任権限パターン

投資家はファンド管理者によるトークン移動を事前承認し、管理者は投資家の署名を必要とせずにストライク時刻に執行します：

┌──────────┐    delegates     ┌────────────────────┐    delegates    ┌──────────┐
│ Investor │ ───────────────→ │ Fund Administrator │ ←────────────── │ Investor │
│    A     │     (USDC)       │     (trusted)      │     (shares)    │    B     │
└──────────┘                  │                    │                 └──────────┘
                              │  executes strike   │
                              │  (atomic txns)     │
                              └────────────────────┘

申込みフロー（USDC → ファンド口数）

Investor wants to invest $100,000 USDC
Current NAV = $1.000234 per share
────────────────────────────────────
1. Investor approves $100,000 USDC delegation
2. At strike time, atomic transaction:
   ├── Transfer $100,000 USDC from investor
   ├── Calculate shares: 100,000 / 1.000234 = 99,976.61
   └── Mint 99,976.61 fund shares to investor
3. Settlement complete in <1 second

換金フロー（ファンド口数 → USDC）

Investor wants to redeem 50,000 shares
Current NAV = $1.000234 per share
────────────────────────────────────
1. Investor approves 50,000 shares delegation
2. At strike time, atomic transaction:
   ├── Burn 50,000 fund shares from investor
   ├── Calculate USDC: 50,000 × 1.000234 = $50,011.70
   └── Transfer $50,011.70 USDC to investor
3. Settlement complete in <1 second

NAVストライクにSolanaを使う理由

Solanaのアーキテクチャは、従来のファンド決済に対して大きな優位性を提供します：

項目	従来型（T+1）	Solana NAVストライク
決済ロジック	振替代理人	アトミックトランザクションバンドリング
決済時間	1〜2日	<1秒
トランザクションコスト	50〜200ドル	<0.01ドル
1日あたりのストライク数	1回	4回以上（設定可能）
価格陳腐化リスク	高い	低い
NAVの透明性	日次終了レポート	オンチェーン、リアルタイム

Solanaのアトミックトランザクションは仲介者を排除しながら、オンチェーンNAVの透明性を備えた即時かつ低コストで安全な決済を実現します。

Token 2022拡張機能によるファンドトークン

SPL Token 2022は、カスタムプログラムなしにコンプライアンスに準拠したファンド口数の発行を可能にする強力な拡張機能を提供します：

ファンド口数に不可欠な拡張機能

デフォルトアカウント状態拡張機能：すべての新しいtoken accountをデフォルトでフリーズ状態に設定し、明示的なホワイトリスト登録（KYC/AMLコンプライアンス）を要求
メタデータ拡張機能：透明性のためにNAV、ストライクスケジュール、AUMをオンチェーンに保存

権限の設定

ミント権限：ファンド管理者（口数発行を制御）
フリーズ権限：ファンド管理者（ホワイトリストを管理）
更新権限：ファンド管理者（NAVメタデータを更新）

デフォルトのフリーズ状態は、法令遵守のために不可欠です。明示的にホワイトリスト登録（KYC確認済み）されたアドレスのみがファンド口数を受け取り、保有できることを保証します。

オンチェーンメタデータフィールド

{
  "name": "Example Money Market Fund",
  "symbol": "EX-MMF",
  "currentNAV": "1.000234",
  "lastStrikeTime": "2024-01-15T14:30:00Z",
  "strikeSchedule": "[\"09:30\", \"12:00\", \"14:30\", \"16:00\"]",
  "totalAUM": "50000000.00",
  "fundType": "Money Market Fund"
}

NAVストライクの完全な実装

NAVストライクエンジンのセットアップ

このガイドでは、NAVストライクエンジンを作成するために@solana/kitライブラリを使用しています。ソースコードにはweb3.jsの実装も見つけることができます。まず、すべてのファンド操作を処理するコアエンジンクラスを作成します：

/**
 * NAV Strikes Engine - Solana Kit Reference Implementation
 *
 * This implementation demonstrates NAV strikes for money market funds on Solana using:
 * - SPL Token 2022 with Default Account State extension for fund shares
 * - Standard USDC for settlement
 * - Atomic transactions for subscription/redemption
 * - Delegated authority pattern for fund administrator
 *
 * Built with @solana/kit (web3.js 2.0)
 *
 * ⚠️ IMPORTANT: This is a reference implementation for educational purposes.
 * Do NOT use in production without proper audits and security reviews.
 */

import {
  Address,
  airdropFactory,
  appendTransactionMessageInstructions,
  createSolanaRpc,
  createSolanaRpcSubscriptions,
  createTransactionMessage,
  generateKeyPairSigner,
  getSignatureFromTransaction,
  KeyPairSigner,
  lamports,
  pipe,
  sendAndConfirmTransactionFactory,
  setTransactionMessageFeePayerSigner,
  setTransactionMessageLifetimeUsingBlockhash,
  signTransactionMessageWithSigners,
  Rpc,
  RpcSubscriptions,
  SolanaRpcApi,
  SolanaRpcSubscriptionsApi
} from "@solana/kit";
import { getCreateAccountInstruction } from "@solana-program/system";
import {
  TOKEN_PROGRAM_ADDRESS,
  getApproveInstruction,
  getTransferCheckedInstruction,
  getMintToInstruction,
  getBurnInstruction,
  findAssociatedTokenPda,
  getCreateAssociatedTokenInstruction
} from "@solana-program/token";
import {
  TOKEN_2022_PROGRAM_ADDRESS,
  getInitializeMintInstruction,
  getInitializeTokenMetadataInstruction,
  getUpdateTokenMetadataFieldInstruction,
  tokenMetadataField,
  getThawAccountInstruction,
  getFreezeAccountInstruction,
  AccountState,
  getMintSize,
  extension,
  getPreInitializeInstructionsForMintExtensions,
  fetchMaybeToken
} from "@solana-program/token-2022";

import { pack } from "@solana/spl-token-metadata";
import { PublicKey } from "@solana/web3.js";

// TLV (Type-Length-Value) sizes for Token-2022 extensions
const TYPE_SIZE = 2;
const LENGTH_SIZE = 2;

import type {
  FundTokenConfig,
  FundState,
  SubscriptionParams,
  RedemptionParams,
  SubscriptionResult,
  RedemptionResult,
  StrikeResult,
  StrikeOrder,
  SolanaClient
} from "./types";

/**
 * Cluster type for explorer links
 */
export type ClusterType = "mainnet-beta" | "devnet" | "testnet" | "localnet";

/**
 * Generate Solana Explorer link for a transaction
 */
export function getExplorerLink(
  signature: string,
  cluster: ClusterType = "localnet"
): string {
  const baseUrl = "https://explorer.solana.com/tx";
  if (cluster === "localnet") {
    return `${baseUrl}/${signature}?cluster=custom&customUrl=http%3A%2F%2Flocalhost%3A8899`;
  }
  return `${baseUrl}/${signature}?cluster=${cluster}`;
}

/**
 * Generate Solana Explorer link for an account/address
 */
export function getAddressExplorerLink(
  addr: string,
  cluster: ClusterType = "localnet"
): string {
  const baseUrl = "https://explorer.solana.com/address";
  if (cluster === "localnet") {
    return `${baseUrl}/${addr}?cluster=custom&customUrl=http%3A%2F%2Flocalhost%3A8899`;
  }
  return `${baseUrl}/${addr}?cluster=${cluster}`;
}

/**
 * Create a Solana client for Kit
 */
export async function createSolanaClient(
  rpcUrl: string = "http://127.0.0.1:8899",
  wsUrl: string = "ws://127.0.0.1:8900"
): Promise<SolanaClient> {
  const rpc = createSolanaRpc(rpcUrl);
  const rpcSubscriptions = createSolanaRpcSubscriptions(wsUrl);
  const sendAndConfirmTransaction = sendAndConfirmTransactionFactory({
    rpc,
    rpcSubscriptions
  });

  return {
    rpc,
    rpcSubscriptions,
    sendAndConfirmTransaction
  };
}

/**
 * NAV Strike Engine - Solana Kit Version
 *
 * Manages the lifecycle of a money market fund on Solana:
 * - Creates fund tokens with Token 2022 extensions
 * - Updates NAV at scheduled strike times
 * - Processes subscription and redemption orders atomically
 */
export class NAVStrikeEngine {
  private client: SolanaClient;
  private fundAdministrator: KeyPairSigner;
  private cluster: ClusterType;

  // Fund state
  private currentNAV: number = 1.0;
  private totalAUM: number = 0;
  private totalSharesOutstanding: number = 0;
  private strikeSchedule: string[] = [];
  private lastStrikeTime: Date = new Date();

  // Order queue
  private pendingOrders: StrikeOrder[] = [];
  private orderCounter: number = 0;

  constructor(
    client: SolanaClient,
    fundAdministrator: KeyPairSigner,
    cluster: ClusterType = "localnet"
  ) {
    this.client = client;
    this.fundAdministrator = fundAdministrator;
    this.cluster = cluster;
  }

  /**
   * Helper to send and confirm transactions with correct typing
   * Works around stricter types in @solana/kit v5+
   */
  // eslint-disable-next-line @typescript-eslint/no-explicit-any
  private async sendTransaction(
    signedTx: any,
    commitment: "confirmed" | "finalized" = "confirmed"
  ): Promise<void> {
    await this.client.sendAndConfirmTransaction(signedTx, { commitment });
  }

  /**
   * Get explorer link for a transaction signature
   */
  getTxExplorerLink(signature: string): string {
    return getExplorerLink(signature, this.cluster);
  }

  /**
   * Get explorer link for an address
   */
  getAddressLink(addr: string): string {
    return getAddressExplorerLink(addr, this.cluster);
  }

  /**
   * Creates a fund share token using Token-2022 with Default Account State and Metadata extensions
   * Fund shares are frozen by default and require whitelisting
   * Metadata stores NAV and fund information onchain
   */
  async createFundToken(
    issuer: KeyPairSigner,
    config: FundTokenConfig
  ): Promise<Address> {
    console.log(
      "\n╔══════════════════════════════════════════════════════════════╗"
    );
    console.log(
      "║              NAV STRIKE - FUND CREATION (Kit)                 ║"
    );
    console.log(
      "╚══════════════════════════════════════════════════════════════╝"
    );
    console.log(`\n🏗️  Creating fund token with Token-2022 + Metadata...`);
    console.log(`   Name: ${config.name}`);
    console.log(`   Symbol: ${config.symbol}`);
    console.log(`   Initial NAV: $${config.initialNAV.toFixed(6)}`);
    console.log(`   Strike Schedule: ${config.strikeSchedule.join(", ")}`);

    // Generate new keypair for the mint
    const mint = await generateKeyPairSigner();
    const decimals = config.decimals ?? 6;

    // Define extensions
    const defaultAccountStateExtension = extension("DefaultAccountState", {
      state: AccountState.Frozen
    });
    const metadataPointerExtension = extension("MetadataPointer", {
      authority: this.fundAdministrator.address,
      metadataAddress: mint.address
    });
    const extensions = [defaultAccountStateExtension, metadataPointerExtension];

    // Calculate mint size without metadata
    const baseMintSize = getMintSize(extensions);

    // Create metadata object to calculate EXACT size using pack()
    // Note: PublicKey is only used here for size calculation, not for transaction building
    const metadataForSizing = {
      mint: new PublicKey(mint.address),
      name: config.name,
      symbol: config.symbol,
      uri: config.uri || "",
      additionalMetadata: [
        ["icon-uri", "link to icon"], // Max NAV format
        ["currentNAV", "999999.999999"], // Max NAV format
        ["lastStrikeTime", "2099-12-31T23:59:59.999Z"], // Max ISO timestamp
        ["strikeSchedule", JSON.stringify(config.strikeSchedule)],
        ["totalAUM", "999999999999999.99"], // Max AUM (quadrillions)
        ["fundType", "Money Market Fund"]
      ] as [string, string][]
    };

    // Calculate exact metadata size using pack()
    const metadataLen = pack(metadataForSizing).length;
    // MetadataExtension TLV overhead: 2 bytes for type, 2 bytes for length
    const metadataExtensionOverhead = TYPE_SIZE + LENGTH_SIZE;

    // Add safety buffer for any encoding overhead
    const totalSpace =
      baseMintSize + metadataLen + metadataExtensionOverhead + 100;
    // Get rent for total space
    const mintRent = await this.client.rpc
      .getMinimumBalanceForRentExemption(BigInt(totalSpace))
      .send();

    // Build create account instruction (with base size, but extra rent for metadata)
    const createAccountIx = getCreateAccountInstruction({
      payer: issuer,
      newAccount: mint,
      lamports: lamports(mintRent),
      space: baseMintSize,
      programAddress: TOKEN_2022_PROGRAM_ADDRESS
    });

    // Get extension initialization instructions
    const preInitIxs = getPreInitializeInstructionsForMintExtensions(
      mint.address,
      extensions
    );

    // Initialize mint instruction (Token 2022)
    const initMintIx = getInitializeMintInstruction({
      mint: mint.address,
      decimals,
      mintAuthority: this.fundAdministrator.address,
      freezeAuthority: this.fundAdministrator.address
    });

    // Initialize metadata instruction
    const initMetadataIx = getInitializeTokenMetadataInstruction({
      metadata: mint.address,
      updateAuthority: this.fundAdministrator.address,
      mint: mint.address,
      mintAuthority: this.fundAdministrator,
      name: config.name,
      symbol: config.symbol,
      uri: ""
    });

    // Build custom metadata field update instructions
    const initialMetadata: [string, string][] = [
      ["currentNAV", config.initialNAV.toFixed(6)],
      ["lastStrikeTime", new Date().toISOString()],
      ["strikeSchedule", JSON.stringify(config.strikeSchedule)],
      ["totalAUM", "0.00"],
      ["fundType", "Money Market Fund"]
    ];

    const updateFieldIxs = initialMetadata.map(([key, value]) =>
      getUpdateTokenMetadataFieldInstruction({
        metadata: mint.address,
        updateAuthority: this.fundAdministrator,
        field: tokenMetadataField("Key", [key]),
        value
      })
    );

    // Get latest blockhash
    const { value: latestBlockhash } = await this.client.rpc
      .getLatestBlockhash()
      .send();

    // Build transaction message
    const transactionMessage = pipe(
      createTransactionMessage({ version: 0 }),
      (tx) => setTransactionMessageFeePayerSigner(issuer, tx),
      (tx) => setTransactionMessageLifetimeUsingBlockhash(latestBlockhash, tx),
      (tx) =>
        appendTransactionMessageInstructions(
          [
            createAccountIx,
            ...preInitIxs,
            initMintIx,
            initMetadataIx,
            ...updateFieldIxs
          ],
          tx
        )
    );

    // Sign and send
    const signedTransaction =
      await signTransactionMessageWithSigners(transactionMessage);
    const signature = getSignatureFromTransaction(signedTransaction);

    await this.sendTransaction(signedTransaction);

    // Update internal state
    this.currentNAV = config.initialNAV;
    this.strikeSchedule = config.strikeSchedule;
    this.lastStrikeTime = new Date();

    console.log(`\n✅ Fund token created: ${mint.address}`);
    console.log(`   Mint Authority: ${this.fundAdministrator.address}`);
    console.log(`   Freeze Authority: ${this.fundAdministrator.address}`);
    console.log(`   Default State: FROZEN (requires whitelisting)`);
    console.log(`   ✨ Metadata: ON-CHAIN`);
    console.log(`   - NAV: $${config.initialNAV.toFixed(6)}`);
    console.log(`   - Schedule: ${config.strikeSchedule.join(", ")}`);
    console.log(`   🔗 Token: ${this.getAddressLink(mint.address)}`);
    console.log(`   🔗 Tx: ${this.getTxExplorerLink(signature)}`);

    return mint.address;
  }

動的メタデータの更新

ファンド口数の場合、currentNAV、lastStrikeTime、totalAUMフィールドは、getUpdateTokenMetadataFieldInstructionを使用して各NAVストライク時にオンチェーンで更新されます。これにより以下が実現します：

リアルタイムNAVの可視性（すべての参加者向け）
すべてのNAV更新のオンチェーン監査証跡
オンチェーンメタデータを読み取れるDeFiプロトコルとの統合

  /**
   * Updates NAV onchain in token metadata
   */
  async updateNAV(fundMint: Address, newNAV: number): Promise<string> {
    const previousNAV = this.currentNAV;
    this.currentNAV = newNAV;
    this.lastStrikeTime = new Date();

    // Build update field instructions
    const updateNavIx = getUpdateTokenMetadataFieldInstruction({
      metadata: fundMint,
      updateAuthority: this.fundAdministrator,
      field: tokenMetadataField("Key", ["currentNAV"]),
      value: newNAV.toFixed(6)
    });

    const updateTimeIx = getUpdateTokenMetadataFieldInstruction({
      metadata: fundMint,
      updateAuthority: this.fundAdministrator,
      field: tokenMetadataField("Key", ["lastStrikeTime"]),
      value: this.lastStrikeTime.toISOString()
    });

    const updateAumIx = getUpdateTokenMetadataFieldInstruction({
      metadata: fundMint,
      updateAuthority: this.fundAdministrator,
      field: tokenMetadataField("Key", ["totalAUM"]),
      value: this.totalAUM.toFixed(2)
    });

    const { value: latestBlockhash } = await this.client.rpc
      .getLatestBlockhash()
      .send();

    const transactionMessage = pipe(
      createTransactionMessage({ version: 0 }),
      (tx) => setTransactionMessageFeePayerSigner(this.fundAdministrator, tx),
      (tx) => setTransactionMessageLifetimeUsingBlockhash(latestBlockhash, tx),
      (tx) =>
        appendTransactionMessageInstructions(
          [updateNavIx, updateTimeIx, updateAumIx],
          tx
        )
    );

    const signedTransaction =
      await signTransactionMessageWithSigners(transactionMessage);
    const signature = getSignatureFromTransaction(signedTransaction);

    await this.sendTransaction(signedTransaction);

    const navChange = ((newNAV - previousNAV) / previousNAV) * 100;
    const changeSymbol = navChange >= 0 ? "▲" : "▼";

    console.log(
      `   NAV Updated: $${previousNAV.toFixed(6)} → $${newNAV.toFixed(
        6
      )} (${changeSymbol}${Math.abs(navChange).toFixed(4)}%)`
    );
    console.log(`   🔗 Explorer: ${this.getTxExplorerLink(signature)}`);

    return signature;
  }

  /**
   * Whitelists an investor by creating their fund account and thawing it
   */
  async whitelistInvestor(
    fundMint: Address,
    investor: Address,
    payer: KeyPairSigner
  ): Promise<Address> {
    console.log(`\n🔓 Whitelisting investor: ${investor.slice(0, 20)}...`);

    // Find the ATA
    const [ata] = await findAssociatedTokenPda({
      mint: fundMint,
      owner: investor,
      tokenProgram: TOKEN_2022_PROGRAM_ADDRESS
    });

    const maybeToken = await fetchMaybeToken(this.client.rpc, ata, {
      commitment: "confirmed"
    });

    const { value: latestBlockhash } = await this.client.rpc
      .getLatestBlockhash()
      .send();

    if (!maybeToken.exists) {
      // Create ATA
      const createAtaIx = getCreateAssociatedTokenInstruction({
        payer,
        owner: investor,
        mint: fundMint,
        ata,
        tokenProgram: TOKEN_2022_PROGRAM_ADDRESS
      });

      const createAtaMsg = pipe(
        createTransactionMessage({ version: 0 }),
        (tx) => setTransactionMessageFeePayerSigner(payer, tx),
        (tx) =>
          setTransactionMessageLifetimeUsingBlockhash(latestBlockhash, tx),
        (tx) => appendTransactionMessageInstructions([createAtaIx], tx)
      );

      const signedCreateAta =
        await signTransactionMessageWithSigners(createAtaMsg);
      await this.sendTransaction(signedCreateAta);
    }

    // Thaw the account
    const thawIx = getThawAccountInstruction({
      account: ata,
      mint: fundMint,
      owner: this.fundAdministrator
    });

    const thawMsg = pipe(
      createTransactionMessage({ version: 0 }),
      (tx) => setTransactionMessageFeePayerSigner(payer, tx),
      (tx) => setTransactionMessageLifetimeUsingBlockhash(latestBlockhash, tx),
      (tx) => appendTransactionMessageInstructions([thawIx], tx)
    );

    const signedThaw = await signTransactionMessageWithSigners(thawMsg);
    await this.sendTransaction(signedThaw);

    console.log(`   Account: ${ata}`);
    console.log(`✅ Investor whitelisted and account thawed`);

    return ata;
  }

  /**
   * Removes an investor from whitelist by freezing their account
   */
  async removeFromWhitelist(
    fundMint: Address,
    investorFundAccount: Address,
    payer: KeyPairSigner
  ): Promise<void> {
    console.log(`\n🔒 Removing from whitelist: ${investorFundAccount}`);

    const { value: latestBlockhash } = await this.client.rpc
      .getLatestBlockhash()
      .send();

    const freezeIx = getFreezeAccountInstruction({
      account: investorFundAccount,
      mint: fundMint,
      owner: this.fundAdministrator
    });

    const freezeMsg = pipe(
      createTransactionMessage({ version: 0 }),
      (tx) => setTransactionMessageFeePayerSigner(payer, tx),
      (tx) => setTransactionMessageLifetimeUsingBlockhash(latestBlockhash, tx),
      (tx) => appendTransactionMessageInstructions([freezeIx], tx)
    );

    const signedFreeze = await signTransactionMessageWithSigners(freezeMsg);
    await this.sendTransaction(signedFreeze);

    console.log(`✅ Account frozen and removed from whitelist`);
  }

  /**
   * Delegates USDC authority to fund administrator for subscription
   */
  async delegateUSDCForSubscription(
    investor: KeyPairSigner,
    usdcMint: Address,
    amount: number
  ): Promise<void> {
    const [investorUSDC] = await findAssociatedTokenPda({
      mint: usdcMint,
      owner: investor.address,
      tokenProgram: TOKEN_PROGRAM_ADDRESS
    });

    console.log(`\n🤝 Delegating USDC for subscription...`);
    console.log(`   Amount: $${amount.toLocaleString()}`);

    const { value: latestBlockhash } = await this.client.rpc
      .getLatestBlockhash()
      .send();

    const approveIx = getApproveInstruction({
      source: investorUSDC,
      delegate: this.fundAdministrator.address,
      owner: investor,
      amount: BigInt(amount * 1e6)
    });

    const approveMsg = pipe(
      createTransactionMessage({ version: 0 }),
      (tx) => setTransactionMessageFeePayerSigner(investor, tx),
      (tx) => setTransactionMessageLifetimeUsingBlockhash(latestBlockhash, tx),
      (tx) => appendTransactionMessageInstructions([approveIx], tx)
    );

    const signedApprove = await signTransactionMessageWithSigners(approveMsg);
    await this.sendTransaction(signedApprove);

    console.log(`✅ USDC delegation approved`);
  }

  /**
   * Delegates fund shares authority to administrator for redemption
   */
  async delegateSharesForRedemption(
    investor: KeyPairSigner,
    fundMint: Address,
    shareAmount: number
  ): Promise<void> {
    const [investorShares] = await findAssociatedTokenPda({
      mint: fundMint,
      owner: investor.address,
      tokenProgram: TOKEN_2022_PROGRAM_ADDRESS
    });

    console.log(`\n🤝 Delegating shares for redemption...`);
    console.log(`   Shares: ${shareAmount.toLocaleString()}`);

    const { value: latestBlockhash } = await this.client.rpc
      .getLatestBlockhash()
      .send();

    const approveIx = getApproveInstruction(
      {
        source: investorShares,
        delegate: this.fundAdministrator.address,
        owner: investor,
        amount: BigInt(Math.floor(shareAmount * 1e6))
      },
      { programAddress: TOKEN_2022_PROGRAM_ADDRESS }
    );

    const approveMsg = pipe(
      createTransactionMessage({ version: 0 }),
      (tx) => setTransactionMessageFeePayerSigner(investor, tx),
      (tx) => setTransactionMessageLifetimeUsingBlockhash(latestBlockhash, tx),
      (tx) => appendTransactionMessageInstructions([approveIx], tx)
    );

    const signedApprove = await signTransactionMessageWithSigners(approveMsg);
    await this.sendTransaction(signedApprove);

    console.log(`✅ Share delegation approved`);
  }

  /**
   * Executes atomic subscription: USDC → Fund Shares at current NAV
   */
  async processSubscription(
    params: SubscriptionParams
  ): Promise<SubscriptionResult> {
    const { fundMint, usdcMint, investor, usdcAmount } = params;

    // Calculate shares at current NAV
    const sharesToMint = usdcAmount / this.currentNAV;
    const shortAddr = `${investor.slice(0, 4)}...${investor.slice(-4)}`;

    console.log(`\n⚡ Processing subscription...`);
    console.log(`   Investor: ${shortAddr}`);
    console.log(`   USDC Amount: $${usdcAmount.toLocaleString()}`);
    console.log(`   NAV: $${this.currentNAV.toFixed(6)}`);
    console.log(`   Shares to mint: ${sharesToMint.toFixed(6)}`);

    // Get token accounts
    const [investorUSDC] = await findAssociatedTokenPda({
      mint: usdcMint,
      owner: investor,
      tokenProgram: TOKEN_PROGRAM_ADDRESS
    });

    const [fundUSDC] = await findAssociatedTokenPda({
      mint: usdcMint,
      owner: this.fundAdministrator.address,
      tokenProgram: TOKEN_PROGRAM_ADDRESS
    });

    const [investorShares] = await findAssociatedTokenPda({
      mint: fundMint,
      owner: investor,
      tokenProgram: TOKEN_2022_PROGRAM_ADDRESS
    });

    const { value: latestBlockhash } = await this.client.rpc
      .getLatestBlockhash()
      .send();

    // Build atomic transaction with both instructions
    // 1. Transfer USDC from investor to fund (using delegated authority)
    const transferUSDCIx = getTransferCheckedInstruction({
      source: investorUSDC,
      mint: usdcMint,
      destination: fundUSDC,
      authority: this.fundAdministrator,
      amount: BigInt(Math.floor(usdcAmount * 1e6)),
      decimals: 6
    });

    // 2. Mint fund shares to investor
    const mintSharesIx = getMintToInstruction(
      {
        mint: fundMint,
        token: investorShares,
        mintAuthority: this.fundAdministrator,
        amount: BigInt(Math.floor(sharesToMint * 1e6))
      },
      { programAddress: TOKEN_2022_PROGRAM_ADDRESS }
    );

    const txMessage = pipe(
      createTransactionMessage({ version: 0 }),
      (tx) => setTransactionMessageFeePayerSigner(this.fundAdministrator, tx),
      (tx) => setTransactionMessageLifetimeUsingBlockhash(latestBlockhash, tx),
      (tx) =>
        appendTransactionMessageInstructions([transferUSDCIx, mintSharesIx], tx) // <- Both happen at the same time
    );

    const signedTx = await signTransactionMessageWithSigners(txMessage);
    const signature = getSignatureFromTransaction(signedTx);

    await this.sendTransaction(signedTx);

    // Update fund state
    this.totalAUM += usdcAmount;
    this.totalSharesOutstanding += sharesToMint;

    console.log(`✅ SUBSCRIPTION SETTLED ATOMICALLY`);
    console.log(`   Shares issued: ${sharesToMint.toFixed(6)}`);
    console.log(`   New AUM: $${this.totalAUM.toLocaleString()}`);
    console.log(`   🔗 Explorer: ${this.getTxExplorerLink(signature)}`);

    return {
      signature,
      usdcAmount,
      sharesIssued: sharesToMint,
      executionNAV: this.currentNAV,
      timestamp: new Date()
    };
  }

  /**
   * Executes atomic redemption: Fund Shares → USDC at current NAV
   */
  async processRedemption(params: RedemptionParams): Promise<RedemptionResult> {
    const { fundMint, usdcMint, investor, shareAmount } = params;

    // Calculate USDC at current NAV
    const usdcToPay = shareAmount * this.currentNAV;
    const shortAddr = `${investor.slice(0, 4)}...${investor.slice(-4)}`;

    console.log(`\n⚡ Processing redemption...`);
    console.log(`   Investor: ${shortAddr}`);
    console.log(`   Shares to redeem: ${shareAmount.toLocaleString()}`);
    console.log(`   NAV: $${this.currentNAV.toFixed(6)}`);
    console.log(`   USDC to pay: $${usdcToPay.toFixed(2)}`);

    // Get token accounts
    const [investorShares] = await findAssociatedTokenPda({
      mint: fundMint,
      owner: investor,
      tokenProgram: TOKEN_2022_PROGRAM_ADDRESS
    });

    const [investorUSDC] = await findAssociatedTokenPda({
      mint: usdcMint,
      owner: investor,
      tokenProgram: TOKEN_PROGRAM_ADDRESS
    });

    const [fundUSDC] = await findAssociatedTokenPda({
      mint: usdcMint,
      owner: this.fundAdministrator.address,
      tokenProgram: TOKEN_PROGRAM_ADDRESS
    });

    const { value: latestBlockhash } = await this.client.rpc
      .getLatestBlockhash()
      .send();

    // Build atomic transaction with both instructions
    // 1. Burn fund shares from investor (using delegated authority)
    const burnSharesIx = getBurnInstruction(
      {
        account: investorShares,
        mint: fundMint,
        authority: this.fundAdministrator,
        amount: BigInt(Math.floor(shareAmount * 1e6))
      },
      { programAddress: TOKEN_2022_PROGRAM_ADDRESS }
    );

    // 2. Transfer USDC from fund to investor
    const transferUSDCIx = getTransferCheckedInstruction({
      source: fundUSDC,
      mint: usdcMint,
      destination: investorUSDC,
      authority: this.fundAdministrator,
      amount: BigInt(Math.floor(usdcToPay * 1e6)),
      decimals: 6
    });

    const txMessage = pipe(
      createTransactionMessage({ version: 0 }),
      (tx) => setTransactionMessageFeePayerSigner(this.fundAdministrator, tx),
      (tx) => setTransactionMessageLifetimeUsingBlockhash(latestBlockhash, tx),
      (tx) =>
        appendTransactionMessageInstructions([burnSharesIx, transferUSDCIx], tx)
    );

    const signedTx = await signTransactionMessageWithSigners(txMessage);
    const signature = getSignatureFromTransaction(signedTx);

    await this.sendTransaction(signedTx);

    // Update fund state
    this.totalAUM -= usdcToPay;
    this.totalSharesOutstanding -= shareAmount;

    console.log(`✅ REDEMPTION SETTLED ATOMICALLY`);
    console.log(`   USDC paid: $${usdcToPay.toFixed(2)}`);
    console.log(`   New AUM: $${this.totalAUM.toLocaleString()}`);
    console.log(`   🔗 Explorer: ${this.getTxExplorerLink(signature)}`);

    return {
      signature,
      sharesRedeemed: shareAmount,
      usdcPaid: usdcToPay,
      executionNAV: this.currentNAV,
      timestamp: new Date()
    };
  }

  /**
   * Queue an order for the next NAV strike
   */
  queueOrder(
    investor: Address,
    orderType: "subscribe" | "redeem",
    amount: number
  ): StrikeOrder {
    const order: StrikeOrder = {
      orderId: `ORD-${++this.orderCounter}`,
      investor,
      orderType,
      amount,
      strikeTime: this.getNextStrikeTime(),
      status: "pending"
    };

    this.pendingOrders.push(order);

    const shortAddr = `${investor.slice(0, 4)}...${investor.slice(-4)}`;

    console.log(`\n📝 Order queued: ${order.orderId}`);
    console.log(`   Investor: ${shortAddr}`);
    console.log(`   Type: ${orderType}`);
    console.log(
      `   Amount: ${
        orderType === "subscribe"
          ? `$${amount.toLocaleString()} USDC`
          : `${amount.toLocaleString()} shares`
      }`
    );

    return order;
  }

  /**
   * Execute NAV strike - update NAV and process all pending orders
   */
  async executeStrike(
    fundMint: Address,
    usdcMint: Address,
    newNAV: number
  ): Promise<StrikeResult> {
    const strikeId = `STRIKE-${Date.now()}`;
    const strikeTime = new Date();

    console.log(
      "\n╔══════════════════════════════════════════════════════════════╗"
    );
    console.log(
      "║                    NAV STRIKE EXECUTION                       ║"
    );
    console.log(
      "╚══════════════════════════════════════════════════════════════╝"
    );
    console.log(`   Strike ID: ${strikeId}`);
    console.log(`   Strike Time: ${strikeTime.toISOString()}`);
    console.log(`   New NAV: $${newNAV.toFixed(6)}`);
    console.log(`   Pending Orders: ${this.pendingOrders.length}`);
    console.log(
      "────────────────────────────────────────────────────────────────"
    );

    // 1. Update NAV
    await this.updateNAV(fundMint, newNAV);

    // 2. Process pending orders
    const signatures: string[] = [];
    let totalUSDCSubscribed = 0;
    let totalSharesMinted = 0;
    let totalSharesRedeemed = 0;
    let totalUSDCPaid = 0;
    let subscriptionsProcessed = 0;
    let redemptionsProcessed = 0;

    const subscriptions = this.pendingOrders.filter(
      (o) => o.orderType === "subscribe" && o.status === "pending"
    );

    const redemptions = this.pendingOrders.filter(
      (o) => o.orderType === "redeem" && o.status === "pending"
    );

    // Process subscriptions
    console.log(`\n📥 Processing ${subscriptions.length} subscriptions...`);
    for (const order of subscriptions) {
      try {
        const result = await this.processSubscription({
          fundMint,
          usdcMint,
          investor: order.investor,
          usdcAmount: order.amount
        });

        order.status = "executed";
        signatures.push(result.signature);
        totalUSDCSubscribed += result.usdcAmount;
        totalSharesMinted += result.sharesIssued;
        subscriptionsProcessed++;
      } catch (error) {
        console.error(`   ❌ Order ${order.orderId} failed:`, error);
        order.status = "failed";
      }
    }

    // Process redemptions
    console.log(`\n📤 Processing ${redemptions.length} redemptions...`);
    for (const order of redemptions) {
      try {
        const result = await this.processRedemption({
          fundMint,
          usdcMint,
          investor: order.investor,
          shareAmount: order.amount
        });

        order.status = "executed";
        signatures.push(result.signature);
        totalSharesRedeemed += result.sharesRedeemed;
        totalUSDCPaid += result.usdcPaid;
        redemptionsProcessed++;
      } catch (error) {
        console.error(`   ❌ Order ${order.orderId} failed:`, error);
        order.status = "failed";
      }
    }

    // Clear executed orders
    this.pendingOrders = this.pendingOrders.filter(
      (o) => o.status === "pending"
    );

    // Print summary
    console.log(
      "\n════════════════════════════════════════════════════════════════"
    );
    console.log(
      "                       STRIKE SUMMARY                            "
    );
    console.log(
      "════════════════════════════════════════════════════════════════"
    );
    console.log(`   Subscriptions: ${subscriptionsProcessed} processed`);
    console.log(`   Total USDC In: $${totalUSDCSubscribed.toLocaleString()}`);
    console.log(`   Shares Minted: ${totalSharesMinted.toFixed(2)}`);
    console.log(`   Redemptions: ${redemptionsProcessed} processed`);
    console.log(`   Shares Burned: ${totalSharesRedeemed.toFixed(2)}`);
    console.log(`   Total USDC Out: $${totalUSDCPaid.toLocaleString()}`);
    console.log(`   New AUM: $${this.totalAUM.toLocaleString()}`);
    console.log(
      `   Shares Outstanding: ${this.totalSharesOutstanding.toFixed(2)}`
    );
    console.log(
      "════════════════════════════════════════════════════════════════\n"
    );

    return {
      strikeId,
      strikeTime,
      nav: this.currentNAV,
      subscriptionsProcessed,
      totalUSDCSubscribed,
      totalSharesMinted,
      redemptionsProcessed,
      totalSharesRedeemed,
      totalUSDCPaid,
      signatures
    };
  }

  /**
   * Get current fund state
   */
  getFundState(fundMint: Address): FundState {
    return {
      fundMint,
      currentNAV: this.currentNAV,
      lastStrikeTime: this.lastStrikeTime,
      totalAUM: this.totalAUM,
      totalSharesOutstanding: this.totalSharesOutstanding
    };
  }

  /**
   * Get current NAV
   */
  getCurrentNAV(): number {
    return this.currentNAV;
  }

  /**
   * Get pending orders
   */
  getPendingOrders(): StrikeOrder[] {
    return [...this.pendingOrders];
  }

  /**
   * Calculate next strike time based on schedule
   */
  getNextStrikeTime(): Date {
    const now = new Date();
    const currentTime = `${now.getHours().toString().padStart(2, "0")}:${now
      .getMinutes()
      .toString()
      .padStart(2, "0")}`;

    for (const strikeTime of this.strikeSchedule) {
      if (strikeTime > currentTime) {
        const [hours, minutes] = strikeTime.split(":");
        const strikeDate = new Date(now);
        strikeDate.setHours(parseInt(hours), parseInt(minutes), 0, 0);
        return strikeDate;
      }
    }

    // Next strike is tomorrow's first strike
    const tomorrow = new Date(now);
    tomorrow.setDate(tomorrow.getDate() + 1);
    const [hours, minutes] = this.strikeSchedule[0].split(":");
    tomorrow.setHours(parseInt(hours), parseInt(minutes), 0, 0);
    return tomorrow;
  }

  /**
   * Airdrops SOL for testing
   */
  async airdropSol(publicKey: Address, amount: number): Promise<void> {
    console.log(
      `\n💰 Airdropping ${amount} SOL to ${publicKey.slice(0, 20)}...`
    );
    const airdrop = airdropFactory({
      rpc: this.client.rpc,
      rpcSubscriptions: this.client.rpcSubscriptions
    });
    await airdrop({
      recipientAddress: publicKey,
      lamports: lamports(BigInt(amount * 1_000_000_000)),
      commitment: "confirmed"
    });
    console.log(`✅ Airdrop complete`);
  }
}

完全な使用例

NAVストライク操作の1日全体を示す完全な例を以下に示します：

/**
 * NAV Strikes Demo - Solana Kit Version
 *
 * Demonstrates multiple daily NAV strikes for a money market fund on Solana.
 * Built with @solana/kit (web3.js 2.0)
 *
 * Run with: npm run demo:kit
 * Requires: solana-test-validator running locally
 *
 * ⚠️ EDUCATIONAL REFERENCE ONLY - NOT FOR PRODUCTION USE
 */

import {
  airdropFactory,
  generateKeyPairSigner,
  lamports,
  KeyPairSigner,
  Address
} from "@solana/kit";
import {
  NAVStrikeEngine,
  createSolanaClient,
  getExplorerLink
} from "../nav-strike-engine";
import {
  createTestUSDC,
  mintTestUSDC,
  getUSDCBalance,
  getFundShareBalance
} from "../test-usdc";
import type { SolanaClient } from "../types";

/**
 * Helper to print section headers
 */
function printHeader(title: string): void {
  console.log("\n");
  console.log(
    "╔══════════════════════════════════════════════════════════════╗"
  );
  console.log(`║  ${title.padEnd(60)}║`);
  console.log(
    "╚══════════════════════════════════════════════════════════════╝"
  );
}

/**
 * Print final balances for all participants
 */
async function printBalances(
  client: SolanaClient,
  fundMint: Address,
  usdcMint: Address,
  participants: { name: string; address: Address }[]
): Promise<void> {
  console.log(
    "\n┌─────────────────────────────────────────────────────────────────┐"
  );
  console.log(
    "│                    FINAL BALANCES                              │"
  );
  console.log(
    "├─────────────────────────────────────────────────────────────────┤"
  );

  for (const { name, address } of participants) {
    const usdcBalance = await getUSDCBalance(client, usdcMint, address);
    const shareBalance = await getFundShareBalance(client, fundMint, address);
    console.log(
      `│  ${name.padEnd(15)} USDC: $${usdcBalance
        .toFixed(2)
        .padStart(10)}  │  Shares: ${shareBalance.toFixed(2).padStart(10)} │`
    );
  }

  console.log(
    "└─────────────────────────────────────────────────────────────────┘"
  );

  // Cost comparison
  console.log(
    "\n┌─────────────────────────────────────────────────────────────────┐"
  );
  console.log(
    "│                    COST COMPARISON                              │"
  );
  console.log(
    "├─────────────────────────────────────────────────────────────────┤"
  );
  console.log(
    "│                        Traditional          Solana NAV Strikes  │"
  );
  console.log(
    "│  ─────────────────────────────────────────────────────────────  │"
  );
  console.log(
    "│  Strikes/Day:              1 (4PM)              4+ (configurable)│"
  );
  console.log(
    "│  Settlement:              T+1/T+2                   Instant     │"
  );
  console.log(
    "│  Pricing:            Unknown til 4PM     Exact NAV at strike    │"
  );
  console.log(
    "│  Compliance:        Manual KYC/AML         Onchain whitelist   │"
  );
  console.log(
    "│  Settlement Risk:         High                    None          │"
  );
  console.log(
    "│  Audit Trail:           Manual                Blockchain        │"
  );
  console.log(
    "└─────────────────────────────────────────────────────────────────┘"
  );
}

/**
 * Main demo function
 */
async function main(): Promise<void> {
  console.log(`
╔══════════════════════════════════════════════════════════════════╗
║                                                                  ║
║   ███╗   ██╗ █████╗ ██╗   ██╗    ███████╗████████╗██████╗       ║
║   ████╗  ██║██╔══██╗██║   ██║    ██╔════╝╚══██╔══╝██╔══██╗      ║
║   ██╔██╗ ██║███████║██║   ██║    ███████╗   ██║   ██████╔╝      ║
║   ██║╚██╗██║██╔══██║╚██╗ ██╔╝    ╚════██║   ██║   ██╔══██╗      ║
║   ██║ ╚████║██║  ██║ ╚████╔╝     ███████║   ██║   ██║  ██║      ║
║   ╚═╝  ╚═══╝╚═╝  ╚═╝  ╚═══╝      ╚══════╝   ╚═╝   ╚═╝  ╚═╝      ║
║                                                                  ║
║        NAV STRIKES - Solana Kit Reference Implementation         ║
║        Built with @solana/kit (web3.js 2.0)                     ║
║                                                                  ║
╚══════════════════════════════════════════════════════════════════╝
  `);

  // ─────────────────────────────────────────────────────────────────
  // SETUP: Connect to local validator
  // ─────────────────────────────────────────────────────────────────
  printHeader("SETUP: Connecting to Local Validator");

  const client = await createSolanaClient();
  console.log("✅ Connected to local validator (http://127.0.0.1:8899)");

  // Create keypairs
  const fundAdmin = await generateKeyPairSigner();
  const investorA = await generateKeyPairSigner();
  const investorB = await generateKeyPairSigner();

  console.log(`\n👤 Fund Administrator: ${fundAdmin.address}`);
  console.log(`👤 Investor A: ${investorA.address}`);
  console.log(`👤 Investor B: ${investorB.address}`);

  // Create airdrop function
  const airdrop = airdropFactory({
    rpc: client.rpc,
    rpcSubscriptions: client.rpcSubscriptions
  });

  // Fund accounts with SOL
  console.log("\n💰 Airdropping SOL to accounts...");

  await airdrop({
    recipientAddress: fundAdmin.address,
    lamports: lamports(10_000_000_000n),
    commitment: "confirmed"
  });
  console.log("   ✅ Fund Admin: 10 SOL");

  await airdrop({
    recipientAddress: investorA.address,
    lamports: lamports(2_000_000_000n),
    commitment: "confirmed"
  });
  console.log("   ✅ Investor A: 2 SOL");

  await airdrop({
    recipientAddress: investorB.address,
    lamports: lamports(2_000_000_000n),
    commitment: "confirmed"
  });
  console.log("   ✅ Investor B: 2 SOL");

  // ─────────────────────────────────────────────────────────────────
  // STEP 1: Create Test USDC
  // ─────────────────────────────────────────────────────────────────
  printHeader("STEP 1: Creating Test USDC");

  const usdcMint = await createTestUSDC(client, fundAdmin, fundAdmin);

  // Mint USDC to participants
  await mintTestUSDC(
    client,
    usdcMint,
    fundAdmin,
    investorA.address,
    500,
    "Investor A"
  );
  await mintTestUSDC(
    client,
    usdcMint,
    fundAdmin,
    investorB.address,
    300,
    "Investor B"
  );
  await mintTestUSDC(
    client,
    usdcMint,
    fundAdmin,
    fundAdmin.address,
    1000,
    "Fund Admin"
  );

  // ─────────────────────────────────────────────────────────────────
  // STEP 2: Create NAV Strike Engine & Fund Token
  // ─────────────────────────────────────────────────────────────────
  printHeader("STEP 2: Creating Fund & NAV Strike Engine");

  const engine = new NAVStrikeEngine(client, fundAdmin, "localnet");

  const fundMint = await engine.createFundToken(fundAdmin, {
    name: "Example Money Market Fund",
    symbol: "EX-MMF",
    uri: "Link to of chain meta data",
    initialNAV: 1.0,
    strikeSchedule: ["09:30", "12:00", "14:30", "16:00"],
    decimals: 6
  });

  // ─────────────────────────────────────────────────────────────────
  // STEP 3: Whitelist Investors
  // ─────────────────────────────────────────────────────────────────
  printHeader("STEP 3: Whitelisting Investors (KYC/AML)");

  await engine.whitelistInvestor(fundMint, investorA.address, fundAdmin);
  await engine.whitelistInvestor(fundMint, investorB.address, fundAdmin);

  // ─────────────────────────────────────────────────────────────────
  // STRIKE 1: 9:30 AM - Initial Subscriptions
  // ─────────────────────────────────────────────────────────────────
  printHeader("STRIKE 1: 9:30 AM - Initial Subscriptions");

  // Investors delegate USDC and queue orders
  await engine.delegateUSDCForSubscription(investorA, usdcMint, 250);
  engine.queueOrder(investorA.address, "subscribe", 250);

  await engine.delegateUSDCForSubscription(investorB, usdcMint, 150);
  engine.queueOrder(investorB.address, "subscribe", 150);

  // Execute strike at $1.00 NAV
  await engine.executeStrike(fundMint, usdcMint, 1.0);

  // ─────────────────────────────────────────────────────────────────
  // STRIKE 2: 12:00 PM - Additional Subscription
  // ─────────────────────────────────────────────────────────────────
  printHeader("STRIKE 2: 12:00 PM - Additional Subscription");

  // Investor A adds more
  await engine.delegateUSDCForSubscription(investorA, usdcMint, 100);
  engine.queueOrder(investorA.address, "subscribe", 100);

  // Execute strike at $1.01 NAV (slight gain from interest)
  await engine.executeStrike(fundMint, usdcMint, 1.01);

  // ─────────────────────────────────────────────────────────────────
  // STRIKE 3: 2:30 PM - Partial Redemption
  // ─────────────────────────────────────────────────────────────────
  printHeader("STRIKE 3: 2:30 PM - Partial Redemption");

  // Investor B redeems 50 shares
  await engine.delegateSharesForRedemption(investorB, fundMint, 50);
  engine.queueOrder(investorB.address, "redeem", 50);

  // Execute strike at $1.02 NAV
  await engine.executeStrike(fundMint, usdcMint, 1.02);

  // ─────────────────────────────────────────────────────────────────
  // STRIKE 4: 4:00 PM - End of Day
  // ─────────────────────────────────────────────────────────────────
  printHeader("STRIKE 4: 4:00 PM - End of Day");

  // No new orders, just NAV update
  await engine.executeStrike(fundMint, usdcMint, 1.03);

  // ─────────────────────────────────────────────────────────────────
  // FINAL: Print Balances
  // ─────────────────────────────────────────────────────────────────
  printHeader("FINAL RESULTS");

  await printBalances(client, fundMint, usdcMint, [
    { name: "Fund Admin", address: fundAdmin.address },
    { name: "Investor A", address: investorA.address },
    { name: "Investor B", address: investorB.address }
  ]);

  // Print fund state
  const fundState = engine.getFundState(fundMint);
  console.log("\n📊 Fund State:");
  console.log(`   Current NAV: $${fundState.currentNAV.toFixed(6)}`);
  console.log(`   Total AUM: $${fundState.totalAUM.toLocaleString()}`);
  console.log(
    `   Shares Outstanding: ${fundState.totalSharesOutstanding.toFixed(2)}`
  );
  console.log(`   Last Strike: ${fundState.lastStrikeTime.toISOString()}`);

  console.log(
    "\n✅ Demo complete! NAV Strikes with Solana Kit working correctly."
  );
  console.log(
    "   View transactions on Solana Explorer (local validator - links shown above)\n"
  );
}

// Run the demo
main().catch((error) => {
  console.error("❌ Demo failed:", error);
  process.exit(1);
});

本番環境への導入にあたっての考慮事項

本番環境にデプロイする前に、以下の点に対処してください：

セキュリティ：プロフェッショナルな鍵管理、マルチシグ制御、およびコードベースの包括的なセキュリティ監査
法令遵守：有価証券の登録、KYC/AMLシステム、移転制限、および必要な報告
鍵管理：適切なバックアップと復旧手順を備えた機関向けカストディソリューション
トランザクション処理：優先手数料、リトライロジック、確認処理、およびRPC冗長性
ファンド運営：権威ある情報源からのNAV算出、カストディアン統合、および照合
モニタリング：リアルタイム追跡、アラート、および自動化された規制報告

次のステップ

SolanaのNAVストライクを理解した後：

Token Extensionsを探索する：追加のコンプライアンス機能のためのパーマネントデリゲートなど、他のToken 2022拡張機能について学ぶ
Token ACLを実装する：コンプライアンスの強化のために、Token ACLを使用してパーミッションレスなThawによる投資家ホワイトリスト管理を検討してください。これにより、投資家がコンプライアンスチェックを通過した後に自動的にアカウントを有効化できるセルフサービスKYC検証が実現し、規制上の管理を維持しながら運用負荷を軽減できます。
DvP決済を学ぶ：有価証券の決済パターンについては、Delivery vs Payment（対価引渡）ガイドを参照
本番アーキテクチャ：堅牢なスケジューリング、モニタリング、および障害復旧システムを設計

まとめ

SolanaのアトミックトランザクションモデルとToken 2022拡張機能は、マネーマーケットファンドの複数回の日次NAVストライクを実装するための強力な基盤を提供します。以下の組み合わせが：

ネイティブなアトミック実行（スマートコントラクトリスクなし）
サブ秒のファイナリティ
ほぼゼロのトランザクションコスト
オンチェーンNAVの透明性
組み込みのコンプライアンス機能（フリーズデフォルト、メタデータ）

Solanaをファンド決済インフラの近代化と、投資家へのより頻繁な取引機会の提供に理想的なプラットフォームとしています。

ただし、この教育目的の参照実装から本番環境に移行するには、セキュリティ、コンプライアンス、カストディ、および運用に関する追加の作業が大幅に必要です。ファンドのトークン化を扱う際は、必ず資格のある法律、規制、および技術の専門家と連携してください。

目次