Published on

Long-Term Support For Calle


OpenSats is thrilled to announce long-term support for our latest grantee, Calle.

Calle is recognized for his ongoing work with Cashu, a free and open-source Chaumian Ecash protocol that greatly improves user transaction privacy and efficiency. He has also been instrumental in the development and maintenance of the popular mint implementation, Nutshell, and the wallet, which supports offline Ecash transactions.

In addition to his work with Cashu, Calle has contributed to other notable projects such as LNbits, LightningTipBot, Electronwall, and various other Lightning tools and libraries. These projects demonstrate Calle's commitment to enhancing the functionality and user experience within the Bitcoin ecosystem.

This LTS grant will support Calle's efforts to further enhance the robustness and performance of the Cashu protocol. Some of his key initiatives will include the introduction of a fee structure to prevent denial of service attacks, implementing a proof of liabilities scheme for auditing mints, and building upon the "multinut payments" concept to improve the utility of smaller Ecash balances.

Our mission with Cashu is to create a robust ecash protocol built for Bitcoin with a focus on simplicity, efficiency, and privacy. Anyone should be able to build open-source applications powered by ecash. And anyone should be able to run them.


OpenSats strives to provide sustainable funding for the builders and maintainers of critical open-source infrastructure within the Bitcoin and Nostr ecosystem.

The OpenSats Long-Term Support program is made possible by generous donors like you. To continue supporting contributors like Calle, please consider donating to the General Fund.