The xDai Chain is a dollar-stablecoin blockchain launched jointly by the MakerDAO Foundation and POA Network. It is also a sidechain compatible with Ethereum, using the stablecoin xDai (exchanged at a 1:1 ratio from decentralized stablecoin Dai on Ethereum) as its base token for transactions and gas payments. It uses the STAKE token and a unique proof-of-stake algorithm—POSDAO—for bookkeeping and governance.

The xDai Chain employs a single-token model for transactions and gas payments, eliminating the need to hold additional ETH for gas payments on the Ethereum mainnet. This enables low-cost, rapid payments with stable fees, making it highly suitable for payment and DeFi applications. In the future, this sidechain model will be expanded to include other stablecoins beyond Dai and other mainnets beyond Ethereum, with STAKE continuing to serve as the governance token for these sidechains.