eNuts
The Idea
eNuts is a Cashu wallet designed by Agron for both Android and iOS, emphasizing simplicity. Based on Cashu, which implements Chaumian Ecash on Bitcoin, eNuts employs Chaumian blind signatures to improve transaction privacy. Additionally, eNuts offers Nostr support, ensuring uncensorable and secure transactions. The goal of eNuts is to offer an accessible and intuitive payment and wallet experience for newcomers while delivering privacy-centered features for advanced users. Even in its early stage, eNuts succeeds in this mission.
Before diving into the design for eNuts, I needed a solid grasp on how Chaumian Ecash on Bitcoin works. I focused on three key user areas: Sending Ecash, understanding blinded signatures, and receiving Ecash on Lightning. To get this understanding, I checked out documentation on GitHub, played around with a few wallets, and talked with some developers. These high level flow charts helped me develop a clearer picture of how designing for Ecash differs from layer 1 and layer 2 bitcoin protocols.
User Experience
In the journey to redefine the Ecash experience, eNuts addresses the nuanced intricacies of Chaumian Ecash and the Cashu protocol head-on. The challenges of ensuring transaction privacy with Chaumian blinded signatures, smooth integration of Lightning support and Nostr, and seamless connection to multiple mints required an unwavering commitment to a user-centered approach.
However, the task did not stop at merely understanding and embedding these advanced features. The key challenge lay in demystifying these complexities, making them easily accessible and understandable for every user. With eNuts, users are freed from the labyrinth of technical jargon and intimidating interfaces. Here, Ecash and Bitcoin meet the elegance of simplified design.
User Interface
In designing eNuts' user interface, the challenge was to simplify Ecash operations like "topping off" or exchanging sats on the Bitcoin Lightning Network into sats on the Cashu protocol, and multi-mint management. The integration of Nostr contact brought its own challenges. We developed a seamless address book and easy payment to npub functionality, ensuring uncensorable and untraceable transactions.
I designed a card-style UI, enhancing the visibility of each mint as distinct "objects." This design allows users to assign a custom emoji to each mint, fostering a personalized memory link.
User Research
We began with a deep dive into the Ecash on Bitcoin world, starting with a comprehensive analysis of existing Cashu projects like nutstash, minibits, and cashu.me. Each app's onboarding, minting, sending, and receiving processes were reviewed, capturing what resonated and what could be improved. In parallel, I kept an eye on the design of another Ecash on Bitcoin project, Fedimint, via their Discord UX channel.
The design challenges were unique, mainly due to the extra interaction step introduced by Ecash — a user must send Bitcoin on lightning to the mint and then retrieve Bitcoin on Cashu. As the designs evolved, platforms like Twitter and Nostr became invaluable feedback channels. The Bitcoin Design Community provided a space for iterative design discussions.
Branding
We drew inspiration from the OGs who paved the way for Ecash – the cryptographers and cypherpunks. I decided to use LCD-style visuals as a way of nodding to the four-decade legacy of blinded signatures, a technique fundamental to Ecash. We were keen on balancing the cypherpunk spirit with the primary tenets of our product: Privacy and Simplicity. By merging the old with the new, our branding underscores the revolution that eNuts brings to the table – blending time-tested cryptography with the accessibility and user-friendliness of the modern digital age.
Accolades
At the Nostrasia 2023 hackathon, eNuts claimed the the Overall Winner title and the top spot in the Builder’s Track. Amidst 120 fellow builders and 37 diverse projects, eNuts won. This win was a nod to the importance of designing with the user in mind —a principle that is at the heart of eNuts.
