$REI REI "Built on Bitcoin" is a first-of-its-kind hybrid Layer-2 powered by Bitcoin and Ethereum. By combining the security, liquidity, fees, user base, and innovation of the two largest blockchain ecosystems, REI closes the gap between Bitcoin as a tool for mass adoption and Ethereum as a hub for innovation. This is achieved through REI's rollup ecosystem, which will use Bitcoin as security while giving users access to all the on- and off-ramps, dapps, stablecoins, NFTs, DeFi, and more enabled by Ethereum's EVM.