Struct Eip712Signer 

pub struct Eip712Signer { /* private fields */ }

An EIP-712 order signer for the Limitless Exchange.

Holds a secp256k1 signing key and the venue exchange address (used as verifyingContract in the EIP-712 domain).

Implementations

impl Eip712Signer

pub fn new(private_key: &str, verifying_contract: &str) -> Result<Self, String>

Create a new signer from a private key and the venue exchange address.

Arguments

• private_key — 0x-prefixed hex private key (32 bytes).
• verifying_contract — 0x-prefixed hex address of venue.exchange.

pub fn wallet_address(&self) -> &str

Get the wallet address derived from the private key.

pub fn sign_hash(&self, order_hash: &[u8; 32]) -> Result<String, String>

Sign an EIP-712 order hash and return the 0x-prefixed hex signature.

Returns a 65-byte ECDSA signature in r || s || v format.

pub fn build_gtc_order( &self, maker_address: &str, token_id: &str, side: OrderSide, price: f64, size: f64, fee_rate_bps: i32, ) -> Result<OrderData, String>

Build and sign a GTC limit order.

Validates all fields, generates a unique monotonic salt, and signs the EIP-712 typed data.

Arguments

• maker_address — 0x-prefixed wallet address (must match the signer’s key)
• token_id — Decimal string representation of the token ID
• side — BUY or SELL
• price — Price between 0 and 1
• size — Number of contracts
• fee_rate_bps — Fee rate in basis points (0–10000)

pub fn build_fok_order( &self, maker_address: &str, token_id: &str, side: OrderSide, amount: f64, fee_rate_bps: i32, ) -> Result<OrderData, String>

Build and sign a FOK market order.