Idex claims to be the first hybrid liquidity DEX that combines an order book model with an automated market maker. It blends the performance and features of a traditional order book model with the security and liquidity of an AMM. Idex takes an innovative approach to decentralized exchanges by combining an off-chain trading engine with on-chain trade settlement. Users benefit from that in several ways.

First, this approach does away with failed trades and wasted money on gas fees, making the trading experience more pleasant and efficient. The instant trade execution means front-running or sandwich attacks are not possible and users can trade without waiting for previous trades to settle. As a result, more advanced order types and trading strategies can be executed since limit orders are possible, opening up arbitrage opportunities with other exchanges.

Idex follows an ambitious roadmap that envisions a multi-chain future for the exchange, which currently runs on Ethereum and Binance Smart Chain. For the remainder of 2021, it plans to launch on second layer solutions and Polkadot and implement a referral. For the future, Idex plans to implement leverage trading and launch on additional layer one and layer two blockchains.

Idex takes a unique approach to combining an order book model with an automated market maker. To execute trades, Idex uses an off-chain trading engine that matches the performance of centralized exchanges and guarantees sequencing. Trades are processed in an off-chain order book. Only when a trade is matched and executed, the transaction is settled on-chain.

In doing so, users benefit from not having to pay additional network costs for placing and canceling orders. Furthermore, placements are processed in real-time, enabling more advanced trading and market-making strategies like stop-loss, post-only and fill-or-kill.

The automated market maker guarantees liquidity by displaying virtual limit orders in the order book together with real limit orders to visualize AMM liquidity in the order book model. Orders are usually settled as AMM only or as a hybrid between the AMM and limit order liquidity.

Idex uses smart contracts to decentralize fund custody and trade settlement. To enable the order book model, the smart contract executes trades off-chain but trades are settled on-chain with a delay. The smart contract acts as escrow and restricts the movement of funds until the settlement is finished. Furthermore, trades are sequenced, and a special function in the smart contract ensures funds cannot be restricted indefinitely. Moreover, the smart contract enforces ownership and authorization, meaning users maintain custody and can make markets without additional infrastructure.