El Salvador passes landmark crypto bill, paving way for Bitcoin-backed bonds El Salvador has passed landmark legislation providing the legal framework for a Bitcoin-backed bond — known as the “Volcano Bond” — that will be used to pay down sovereign debt and fund the construction of its proposed “Bitcoin City.” The bill also includes a legal framework for all digital assets that are not Bitcoin, in addition to those issued on Bitcoin, and creates a new regulatory agency that will be in charge of applying the securities law and providing protection from bad actors.