Throttle is the commerce engine in the middle. These are the processors, tax engines, carriers, and apps it talks to — each page says what the integration does, how to switch it on, and where it stops.
Processors and wallets you connect per environment, with routing between them.
Calculate tax on the cart and record it with the engine that files your returns.
Live carrier rates at checkout and order handoff to the warehouse.
Purchase events for ad platforms, and customer data for email and SMS.
Ask about orders, customers, and revenue from the assistant you already use.