Odaily News According to official news, Superposition, a DeFi native L3 project based on Arbitrum One, has launched the first phase of the testnet. The project uses the Arbitrum Orbit technology stack and Stylus to provide a low-cost and fast DeFi experience. Its first DApp on the chain is Longtail, an Arbitrum ecosystem V3 AMM that follows the centralized liquidity model launched by Uniswap. It is also said to be the first AMM built on Arbitrum Stylus. Superposition is built by Fluidity Labs and includes an innovative on-chain order book focused on controlling order flow, with faster execution, shared and permissionless liquidity, account abstraction, and zero-fee features, while providing benefits to liquidity providers and traders.