Cashu is a lightweight, privacy‑preserving ecash system that runs on top of the Lightning Network and settles on‑chain. It uses zero‑knowledge proofs to hide the value of a transfer while remaining fully traceable when required.
Cashu is an ecash protocol that allows you to mint, transfer, and spend sats without revealing the amount or the sender/receiver in public transactions. It leverages the Lightning Network for instant settlement on nodes. Think of it as a privacy‑preserving bearer instrument that can be minted and redeemed across on the Lightning network.
At the core of Cashu is a zero‑knowledge range proof that proves the value of a note without exposing it. This means you can pay for goods or services with a Cashu note and the recipient can verify that the note contains sufficient value, while the transaction remains private on‑chain.
Cashu uses a set of “notes” minted by a mint and signed with a unique key. Each note contains an amount and a unique identifier that the mint keeps encrypted. Transfers are executed with the Lightning Network, and does require a mint to mint notes and therefore requires some level of trust in the mint.
Several wallet applications support Cashu. Below are quick links to some popular ones:
To begin using Cashu, you’ll need a Lightning‑ready wallet that supports the protocol. Most of the
wallets listed above have a Cashu switch or integration. Once installed, create a new Cashu
account, mint a few notes, and start experimenting.