xDeFi is a well established DeFi protocol stack.Many best practices are introduced in xDeFi ecosystem, including but restricted to xDEX as one of optimized AMM DEXes, xHalfLife as a money stream protocol for delayed unlocking of tokens, xOption as a European call and put option with AMM pools, xPerp as a perpetual protocol with shadow AMM, xSTA as a stable coin minted from crypto assets, xNFTEX as an NFT Market with Highly Liquidity, and any other DeFi building blocks which are essential for a well-ordered market.