Chain-key USDT (ckUSDT), a multi-chain USDT twin on the Internet Computer, is an ICRC-1-compliant token that is backed 1:1 by USDT such that 1 ckUSDT can always be redeemed for 1 USDT and vice versa. The ckETH minter canister is responsible for both minting ckUSDT tokens when users transfer USDT to its control and burning ckUSDT when handling USDT retrieval requests. ckUSDT transactions are facilitated through a ledger canister, which in conjunction with archive canisters, tracks ckUSDT account balances and transaction history between accounts. An index canister provides access to ckUSDT transactions associated with individual accounts.