FXPool

The FXPools are custom "Protocol Pools" built on top the Balancer V2 Vault. See the Balancer docs here to learn more about this pool type.

The FXPool implements its own custom "bonding curve" via three main hooks that are called by the Balancer v2 Vault, namelyonJoinPool (called on LP deposit), onExitPool (called on LP withdrawal) and onSwap (called when swapping one token for another).

It is important to note that the FXPools only define custom logic via these three hooks and do not hold idle token balances (learn how the Balancer V2 Vault separates token accounting and logic).