On-Chain Orderbook

Overview

Flur's orderbook architecture is built on a fully decentralized, blockchain-based system that eliminates the need for intermediaries in trading. By storing all orders directly on the blockchain and having miners validate every trade execution, the system ensures maximum transparency and security. The fully on-chain approach eliminates these concerns since all order matching and execution is handled trustlessly through smart contracts and validated by miners. This approach fundamentally differs from traditional PSBT-based marketplaces, which often rely on off-chain verification processes that can be susceptible to data corruption or manipulation.

Key Features

• Fully On-Chain: All order data is stored and executed directly on the blockchain
• Partial Fills: Contracts natively support partial fills on both sides of the orderbook
• Permissionless: Orders can be executed by anyone without third-party approval
• Trustless: No reliance on private databases or centralized infrastructure
• Atomic Execution: Ensures that trades either complete fully with the exact specified tokens or fail entirely, eliminating the risk of partial or incorrect executions

Technical Implementation

Unlike traditional orderbook systems that use PSBT (Partially Signed Bitcoin Transactions) with SIGHASH_SINGLE|ANYONECANPAY signatures stored in private databases, Flur takes a fundamentally different approach:

• Leverages OP_CAT covenants for order creation and management
• Utilizes the sCrypt compiler for smart contract implementation
• Ensures all order data and execution logic remains on-chain

Smart Contracts

The orderbook introduces the following smart contracts:

• FXPCat20Buy: (source code (opens in a new tab)) Handles buy order creation and execution with price scaling support
• FXPCat20Sell: (source code (opens in a new tab)) Manages sell order placement and fulfillment
• FXPSellGuard: (source code (opens in a new tab)) Provides security checks for sell orders
• FXPBuyGuard: (source code (opens in a new tab)) Implements protection mechanisms for buy orders
• FXPOpenMinter: (source code (opens in a new tab)) Handles token minting operations

The orderbook smart contracts include an incentivized mechanism for market makers to provide liquidity by offering Flur Experience Points (FXP) to order makers after a trade is fully executed. To learn more about the FXP token, please refer to the Flur Experience Points page.