/**
 * Compute XXH3 128-bit hash of the input data.
 *
 * @param data - Input data as Uint8Array
 * @param seed - Optional seed value (default: 0)
 * @returns 128-bit hash as a single BigInt (high 64 bits << 64 | low 64 bits)
 */
export declare function XXH3_128(data: Uint8Array, seed?: bigint): bigint;
/**
 * Convert a 128-bit hash (BigInt) to a 16-byte Uint8Array.
 *
 * @param hash128 - 128-bit hash as BigInt
 * @returns 16-byte Uint8Array in little-endian byte order
 */
export declare function xxh128ToBytes(hash128: bigint): Uint8Array;