Is dYdX built on Ethereum?

Could you please clarify for me, is the platform dYdX actually constructed on the Ethereum blockchain? I'm interested in understanding its underlying technology and infrastructure. Does it leverage the security and scalability features of Ethereum? Additionally, does this mean that transactions on dYdX are secured by the Ethereum network and its consensus mechanisms? It would be helpful if you could provide some insight into this aspect of dYdX's operation. Thank you for your assistance in clarifying this matter.