Orderbook State

The Orderbook State account tracks global order execution state for a pool.

It stores:

• Core metadata
• Pool references
• Matching configuration
• order_id counter (u64)

This counter increments every time a new TradeFutures instruction executes.

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Account Creation

The orderbook is a program-owned account, not a PDA.

It is created using:

SystemProgram.createAccount({
  fromPubkey: authority.publicKey,
  newAccountPubkey: orderbookKeypair.publicKey,
  space: ORDERBOOK_STATE_LEN,
  lamports,
  programId: PROGRAM_ID,
});

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Account Size

const ORDERBOOK_STATE_LEN = 1 + (32 * 5) + 8; // 169 bytes

Layout:

Field	Size
is_initialized	1
5 Pubkeys	160
order_id (u64)	8

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Reading Current Order ID

const orderbookData = await connection.getAccountInfo(orderbookKeypair.publicKey);

const orderIdOffset = 1 + (32 * 5);
const currentOrderId = orderbookData.data.readBigUInt64LE(orderIdOffset);

This currentOrderId must be used when deriving:

• Deal PDA
• Trade execution

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Lifecycle Role

The orderbook:

• Tracks sequential deal IDs
• Prevents duplicate deal creation
• Ensures deterministic PDA derivation
• Coordinates matching state

Without it, TradeFutures cannot execute.

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