Tracking changes in Pump.fun global state (initialVirtualTokenReserves, initialVirtualSolReserves, initialRealTokenReserves, tokenTotalSupply, feeBasisPoints).

rpc_fetch_pump_global_state.ts

import * as web3 from "@solana/web3.js";
import bs58 from "bs58";

//////////////////////////////////////////////////

function readBytes(buf: Buffer, offset: number, length: number): Buffer {
  const end = offset + length;
  if (buf.byteLength < end) throw new RangeError("range out of bounds");
  return buf.subarray(offset, end);
}

function readBigUintLE(buf: Buffer, offset: number, length: number): bigint {
  switch (length) {
    case 1: return BigInt(buf.readUint8(offset));
    case 2: return BigInt(buf.readUint16LE(offset));
    case 4: return BigInt(buf.readUint32LE(offset));
    case 8: return buf.readBigUint64LE(offset);
  }
  throw new Error(`unsupported data size (${length} bytes)`);
}

function readBoolean(buf: Buffer, offset: number, length: number): boolean {
  const data = readBytes(buf, offset, length);
  for (const b of data) {
    if (b) return true;
  }
  return false;
}

function readPublicKey(buf: Buffer, offset: number): web3.PublicKey {
  return new web3.PublicKey(readBytes(buf, offset, web3.PUBLIC_KEY_LENGTH));
}

//////////////////////////////////////////////////

const PUMP_PROGRAM_ID = new web3.PublicKey("6EF8rrecthR5Dkzon8Nwu78hRvfCKubJ14M5uBEwF6P");

interface PumpGlobalState {
  initialized: boolean
  authority: web3.PublicKey
  feeRecipient: web3.PublicKey
  initialVirtualTokenReserves: bigint
  initialVirtualSolReserves: bigint
  initialRealTokenReserves: bigint
  tokenTotalSupply: bigint
  feeBasisPoints: bigint
}

// Calculated as the first 8 bytes of: `sha256("account:Global")`.
const PUMP_GLOBAL_STATE_SIGNATURE = Uint8Array.from([0xa7, 0xe8, 0xe8, 0xb1, 0xc8, 0x6c, 0x72, 0x7f]);
const PUMP_GLOBAL_STATE_SIZE = 0x69;
const PUMP_GLOBAL_STATE_OFFSETS = {
  INITIALIZED: 0x08,
  AUTHORITY: 0x09,
  FEE_RECIPIENT: 0x29,
  INITIAL_VIRTUAL_TOKEN_RESERVES: 0x49,
  INITIAL_VIRTUAL_SOL_RESERVES: 0x51,
  INITIAL_REAL_TOKEN_RESERVES: 0x59,
  TOKEN_TOTAL_SUPPLY: 0x61,
  FEE_BASIS_POINTS: 0x69,
};

function decodePumpGlobalState(data: Buffer): PumpGlobalState {
  const idlSignature = readBytes(data, 0, PUMP_GLOBAL_STATE_SIGNATURE.byteLength);
  if (idlSignature.compare(PUMP_GLOBAL_STATE_SIGNATURE) !== 0) {
    throw new Error("unexpected global state IDL signature");
  }

  return {
    initialized: readBoolean(data, PUMP_GLOBAL_STATE_OFFSETS.INITIALIZED, 1),
    authority: readPublicKey(data, PUMP_GLOBAL_STATE_OFFSETS.AUTHORITY),
    feeRecipient: readPublicKey(data, PUMP_GLOBAL_STATE_OFFSETS.FEE_RECIPIENT),
    initialVirtualTokenReserves: readBigUintLE(data, PUMP_GLOBAL_STATE_OFFSETS.INITIAL_VIRTUAL_TOKEN_RESERVES, 8),
    initialVirtualSolReserves: readBigUintLE(data, PUMP_GLOBAL_STATE_OFFSETS.INITIAL_VIRTUAL_SOL_RESERVES, 8),
    initialRealTokenReserves: readBigUintLE(data, PUMP_GLOBAL_STATE_OFFSETS.INITIAL_REAL_TOKEN_RESERVES, 8),
    tokenTotalSupply: readBigUintLE(data, PUMP_GLOBAL_STATE_OFFSETS.TOKEN_TOTAL_SUPPLY, 8),
    feeBasisPoints: readBigUintLE(data, PUMP_GLOBAL_STATE_OFFSETS.FEE_BASIS_POINTS, 8),
  };
}

//////////////////////////////////////////////////

(async (rpcUrl: string) => {

  const conn = new web3.Connection(rpcUrl, "confirmed");

  conn.onProgramAccountChange(PUMP_PROGRAM_ID, (info: web3.KeyedAccountInfo, ctx: web3.Context) => {
    let state: PumpGlobalState | null = null;
    try {
      state = decodePumpGlobalState(info.accountInfo.data);
    } catch (e) {}
    if (!state) return null;

    console.log(ctx.slot, "|", info.accountId.toBase58());
    console.dir(state);
    console.log();
  }, undefined, [
    { dataSize: PUMP_GLOBAL_STATE_SIGNATURE.byteLength + PUMP_GLOBAL_STATE_SIZE },
    { memcmp: { offset: 0, bytes: bs58.encode(PUMP_GLOBAL_STATE_SIGNATURE) } },
  ]);

  //
  //   --- OUTPUT ---
  //
  //     273403135 | 4wTV1YmiEkRvAtNtsSGPtUrqRYQMe5SKy2uB4Jjaxnjf
  //     {
  //       initialized: true,
  //       authority: PublicKey [PublicKey(DCpJReAfonSrgohiQbTmKKbjbqVofspFRHz9yQikzooP)] {
  //         _bn: BN { negative: 0, words: [Array], length: 10, red: null }
  //       },
  //       feeRecipient: PublicKey [PublicKey(CebN5WGQ4jvEPvsVU4EoHEpgzq1VV7AbicfhtW4xC9iM)] {
  //         _bn: BN { negative: 0, words: [Array], length: 10, red: null }
  //       },
  //       initialVirtualTokenReserves: 1073000000000000n,
  //       initialVirtualSolReserves: 30000000000n,
  //       initialRealTokenReserves: 793100000000000n,
  //       tokenTotalSupply: 1000000000000000n,
  //       feeBasisPoints: 100n
  //     }
  //
  //   --------------
  //

})(process.env.SOL_RPC_URL || "https://mainnet.helius-rpc.com/?api-key=00000000-0000-0000-0000-000000000000");

@nshen 113 used to be the correct dataSize, but as it stands, you're right (dataSize is now 512).

Recently, they've been making some changes to the Pump.fun program.
For the sake of completeness, here's the updated structure:

[{
  "name": "Global",
  "discriminator": [167, 232, 232, 177, 200, 108, 114, 127],
  // └──► Buffer.from("a7e8e8b1c86c727f", "hex")

  "type": {
    "kind": "struct",
    "fields": [
      { "name": "initialized",                    "type": "bool"                   },
      //         └──► true
      { "name": "authority",                      "type": "pubkey"                 },
      //         └──► "FFWtrEQ4B4PKQoVuHYzZq8FabGkVatYzDpEVHsK5rrhF"
      { "name": "fee_recipient",                  "type": "pubkey"                 },
      //         └──► "62qc2CNXwrYqQScmEdiZFFAnJR262PxWEuNQtxfafNgV"
      { "name": "initial_virtual_token_reserves", "type": "u64"                    },
      //         └──► 1073000000000000
      { "name": "initial_virtual_sol_reserves",   "type": "u64"                    },
      //         └──► 30000000000
      { "name": "initial_real_token_reserves",    "type": "u64"                    },
      //         └──► 793100000000000
      { "name": "token_total_supply",             "type": "u64"                    },
      //         └──► 1000000000000000
      { "name": "fee_basis_points",               "type": "u64"                    },
      //         └──► 100

      /* ┌────────────── ➕ ➕ ➕ ➕ ➕ ➕ ➕ ➕ ➕ ➕ ➕ ➕ ➕ ➕ ➕ ──────────────┐ */
      { "name": "withdraw_authority",             "type": "pubkey"                 },
      //         └──► "39azUYFWPz3VHgKCf3VChUwbpURdCHRxjWVowf5jUJjg"
      { "name": "enable_migrate",                 "type": "bool"                   },
      //         └──► false
      { "name": "pool_migration_fee",             "type": "u64"                    },
      //         └──► 15000001
      { "name": "creator_fee",                    "type": "u64"                    },
      //         └──► 0
      { "name": "fee_recipients",                 "type": {"array": ["pubkey", 7]} },
      //         └──► [
      //           "7VtfL8fvgNfhz17qKRMjzQEXgbdpnHHHQRh54R9jP2RJ",
      //           "7hTckgnGnLQR6sdH7YkqFTAA7VwTfYFaZ6EhEsU3saCX",
      //           "9rPYyANsfQZw3DnDmKE3YCQF5E8oD89UXoHn9JFEhJUz",
      //           "AVmoTthdrX6tKt4nDjco2D775W2YK3sDhxPcMmzUAmTY",
      //           "CebN5WGQ4jvEPvsVU4EoHEpgzq1VV7AbicfhtW4xC9iM",
      //           "FWsW1xNtWscwNmKv6wVsU1iTzRN6wmmk3MjxRP5tT7hz",
      //           "G5UZAVbAf46s7cKWoyKu8kYTip9DGTpbLZ2qa9Aq69dP",
      //         ]

      // { "name": "__padding1", "type": {"array": ["u8", 126]} }
      /* └────────────── ➕ ➕ ➕ ➕ ➕ ➕ ➕ ➕ ➕ ➕ ➕ ➕ ➕ ➕ ➕ ──────────────┘ */
    ]
  }
}]

so cool @rubpy would you mind telling me how you know that?
I randomly tried lots of numbers yesterday.

{
  initialized: true,
  authority: PublicKey [PublicKey(FFWtrEQ4B4PKQoVuHYzZq8FabGkVatYzDpEVHsK5rrhF)] {
    _bn: BN { negative: 0, words: [Array], length: 10, red: null }
  },
  feeRecipient: PublicKey [PublicKey(62qc2CNXwrYqQScmEdiZFFAnJR262PxWEuNQtxfafNgV)] {
    _bn: BN { negative: 0, words: [Array], length: 10, red: null }
  },
  initialVirtualTokenReserves: 1073000000000000n,
  initialVirtualSolReserves: 30000000000n,
  initialRealTokenReserves: 793100000000000n,
  tokenTotalSupply: 1000000000000000n,
  feeBasisPoints: 100n,
  withdrawAuthority: PublicKey [PublicKey(39azUYFWPz3VHgKCf3VChUwbpURdCHRxjWVowf5jUJjg)] {
    _bn: BN { negative: 0, words: [Array], length: 10, red: null }
  },
  enableMigrate: false,
  poolMigrationFee: 15000001n,
  creatorFee: 0n,
  feeRecipients: [
    PublicKey [PublicKey(7VtfL8fvgNfhz17qKRMjzQEXgbdpnHHHQRh54R9jP2RJ)] {
      _bn: [BN]
    },
    PublicKey [PublicKey(7hTckgnGnLQR6sdH7YkqFTAA7VwTfYFaZ6EhEsU3saCX)] {
      _bn: [BN]
    },
    PublicKey [PublicKey(9rPYyANsfQZw3DnDmKE3YCQF5E8oD89UXoHn9JFEhJUz)] {
      _bn: [BN]
    },
    PublicKey [PublicKey(AVmoTthdrX6tKt4nDjco2D775W2YK3sDhxPcMmzUAmTY)] {
      _bn: [BN]
    },
    PublicKey [PublicKey(CebN5WGQ4jvEPvsVU4EoHEpgzq1VV7AbicfhtW4xC9iM)] {
      _bn: [BN]
    },
    PublicKey [PublicKey(FWsW1xNtWscwNmKv6wVsU1iTzRN6wmmk3MjxRP5tT7hz)] {
      _bn: [BN]
    },
    PublicKey [PublicKey(G5UZAVbAf46s7cKWoyKu8kYTip9DGTpbLZ2qa9Aq69dP)] {
      _bn: [BN]
    }
  ]
}