The Cashu protocol introduces a novel approach to enhancing Bitcoin privacy by utilizing a Layer 2 eCash system. This protocol employs blind signatures to obscure transaction details, allowing users to transfer satoshis via the Lightning Network without leaving on-chain records. Inspired by David Chaum’s eCash, Cashu operates on a mint-wallet model, enabling merchants to accept payments through BTCPay Server. Despite its privacy features, Cashu does not fully anonymize transactions, as metadata such as IP addresses can still be tracked. To achieve greater privacy, users are advised to use Cashu in conjunction with Tor or a mixer. It is important to note that Cashu functions as a bearer asset system, meaning that losing the wallet results in the loss of funds.