useful-links

Environments

https://xexchange.com - mainnet exchange
https://devnet.xexchange.com - devnet exchange stack closely follows a subset of the mainnet setup, with high confidence new features rolled out close to the mainnet rollouts; used as the go to environment for developers to try out their features and integrations.
https://testnet.xexchange.com - testnet exchange stack can loosely follow the mainnet setup, with highly experimental new features rolled out way ahead of mainnet rollouts; used for early and wildly experimental development efforts.

https://github.com/multiversx/mx-exchange-sc - majority of the base xExchange contracts (liquidity pools, farms, staking, etc.)
https://github.com/multiversx/mx-contracts-rs - various purpose contracts out of which xExchange uses some
https://github.com/multiversx/mx-exchange-tools-sc - smart contracts for advanced interactions with base xExchange contracts
https://github.com/multiversx/mx-subscription-fee-rs - subscription service smart contracts for managing paid features