Acala USD (aUSD) is a stablecoin protocol designed to deliver a decentralized, cross-chain stable currency and to act as the native stablecoin for the Polkadot and Kusama ecosystems. aUSD is issued using multiple reserve assets. This structure lets holders of those reserve assets earn, use, trade, and access other services without being exposed to price fluctuations, while still keeping ownership of their reserve assets. Acala USD is pegged to the US Dollar. aUSD can be integrated trustlessly into any blockchain linked to Polkadot or Kusama, along with the applications running on those chains. It can also be brought across chains on other connected blockchain networks.

Anyone can mint aUSD with approved reserve assets, and every aUSD is supported by surplus reserve value (collateral assets). Since these reserve assets are inherently cross-chain, they may include Polkadot assets (DOT and DOT derivatives), KSM and KSM derivatives such as LKSM, Acala’s native token ACA, and Karura’s native token KAR. Looking ahead, the protocol may also take parachain assets and cross-chain assets like Bitcoin (BTC) and Ether (ETH) as collateral, as long as they satisfy the risk requirements and are approved through Acala governance. 

The aUSD stablecoin protocol runs on Acala for the Polkadot ecosystem and on Karura for the Kusama ecosystem.