Add eCash related content and reference designs

[sethwynne]

I'm looking for feedback from the community as to whether eCash related content and reference designs should be added to the guide. All thoughts, suggestions, and concerns are welcome!

Overview

Theres been an active community building products and services that use eCash including the Fedimint protocol currently used by Fedi and wallets including Cashu, Nutstash and more recently Minibits.

Additionally there was a recent announcement by the Human Rights Foundation that includes a bounty of 2 BTC split between 4 different scenarios that use eCash.

I believe we'll continue to see additional products and services built using eCash as more organizations, developers and designers take an interest in eCash as they understand and explore its primary benefits of privacy and scalability, and how the use of eCash can further the adoption of Bitcoin and work towards solutions to unique problems.

Note that theres been an ongoing collaboration between the Bitcoin Design community and the Fedimint project since April 2023.

Additions

I imagine content and reference designs could touch numerous areas of the guide. Possible areas include but are not limited to:

1. Bitcoin technology primer
2. Reference designs - add 'Fedimint wallet', 'Community banking wallet' or something similar as a new section. This wallet type currently won't merge well with the 'Daily spending wallet' section as theres references to wallets being self-custodial
3. Reference designs - add 'Cashu wallet' or something similar as a new section. This wallet type currently won't merge well with the 'Daily spending wallet' section as theres references to wallets being self-custodial
4. How it works
5. Glossary

Content and reference design considerations

A few items the community can discuss to include in the guide (but not limited to):

1. The distinction between wallets that use a progressive web app (PWA) vs native approach, and drill into the advantages and disadvantages to each. I believe we'll see more explorations and conversation in this area due to recent issues with Apple not allowing specific functionality in the Damus app that uses the Nostr protocol.
2. UI reference designs for tasks including administering federations (the guardian role) and maintaining a Lightning gateway - are these appropriate for the guide?
3. 'eCash' terminology - theres been good conversation on the Bitcoin Design Discord server regarding the use of the term 'eCash'. Community agreement on best practices regarding terminology for specific scenarios and contexts will help add clarity and consistency for designers and builders.

I imagine as people start discussion additional ideas for content will come up but feel this is a decent starting point to kick things off.

[GBKS]

Thanks for posting this issue. Could you please move it into the guide repo? This meta repo here is more for organizational stuff for the community. I'll respond to the issue itself there.

[moneyball]

Makes sense to me.

Although PWA vs. native apps seems orthogonal to ecash, so I'm not sure why it is listed here. Separate from ecash it seems like the BDC needs to evaluate whether the BDG should cover such a topic.

[GBKS]

I think it could be a nice addition. A few thoughts:

• Since it is a custodial solution, it would be important to provide really good framing of the trade-offs and what problems and benefits result from them.
• I don't see the progressive web app discussion as tightly linked to eCash and would not include it here
• Regarding reference designs, I think the Daily spending wallet will remain the most complete one, and other reference designs focus on the unique user flows of those products (no need to repeat). This actually simplifies the creation of additional reference designs.

One way to go about this could be:

• Add a glossary definition as a starting point
• Host a Learning bitcoin & design call to go over the basics with a wider group
• Create the How it works page
• Create a very simple reference design with just the unique considerations and flows that are distinct from reference designs we already have (like entering/exiting)
• Iterate over time as needed, with feedback from the broader community

As far as priorities for the guide, I personally would like to see other tasks get done first (like our current savings wallet revisions, and the merchant section (which has never really taken of)), but if someone is enthusiastic about eCash and wants to add this content, please go ahead, I'm all for it.