Consider alternative scheme for DAP

[mistermoe]

After hearing some feedback from folks, using a scheme that is effectively identical to email addresses (e.g. moegrammer@cash.app) is probably not a good idea given the likelihood of people thinking it's an actual email address when it in fact isn't. This in-turn can cause confusion and poor UX which effectively defeats the purpose behind DAPs altogether.

alternatives to consider would be:

• dap:moegrammer:cash.app (props to Chris Meyers for the suggestion)
• moegrammer$cash.app

[decentralgabe]

I dig <name>$<domain.tld>

[mistermoe]

And so it will be @decentralgabe !

[decentralgabe]

As an alternative what about a DID path? Like did:web:cash.app/moegrammer it's uglier but perhaps we could specify a deterministic mapping to be conformant to the DID Web spec

[frankhinek]

a couple other ideas to consider:

• moegrammer:cash.app
• moegrammer<>cash.app

or go with the approach UMA took which is to prepend a $: $moegrammer@cash.app

IMHO, using a currency symbol is suboptimal as the text visually runs together and isn't obviously delimited as is the case with the @ symbol.

If we did go with $ as a delimiter, should the spec allow a variety of currency symbols to be used so that it isn't USA / US Dollar centric?

moegrammer$cash.app moegrammer₿cash.app moegrammer€cash.app moegrammer£cash.app moegrammer¥cash.app moegrammer₪cash.app

[frankhinek]

Another thing to consider with $:

• The "$" symbol is commonly found on keyboard layouts designed for English-speaking countries, such as the United States, United Kingdom, Canada, and Australia.
• In many European countries, the "$" symbol is not typically included on the primary keyboard layout. Instead, users may need to use a special key combination or switch to a secondary keyboard layout (e.g., US layout) to input the "$" symbol.
• Keyboard layouts in Latin American countries, such as Mexico, Argentina, and Brazil, often include the "$" symbol, as it is commonly used in their currencies and financial transactions.
• The inclusion of the "$" symbol on keyboard layouts in Asian countries varies. Some countries, like Japan and South Korea, have the "$" symbol on their primary keyboard layouts, while others may require users to switch to a secondary layout or use a special key combination.
• Keyboard layouts designed for Arabic-speaking countries generally do not include the "$" symbol on the primary layout. Users in these regions may need to switch to a different keyboard layout or use a special key combination to input the symbol.
• Keyboard layouts for languages that use the Cyrillic script, such as Russian, Ukrainian, and Serbian, typically do not include the "$" symbol on the primary layout.

In contrast, : and @ are included on most global keyboard layouts. Each region also includes at least some currency symbol on their keyboards, so using it as a delimiter would also work without requiring people to use a special key combination or switch keyboard layouts to input a DAP.

[frankhinek]

Here's another idea that is similar to email addresses but changes the order to ensure that a DAP cannot be mistaken for an email:

@cash.app/moegrammer @didpay.xyz/moegrammer

From a semantic standpoint, it also makes sense if you read it as:

• "At cash.app there is a paytag of moegrammer that I want to pay."
• "At yellowcard.io there is a paytag of ernest that I want to pay."

Taking this approach means that providers are free to use currency symbols ($, ₿, €, etc.) in their paytags without creating parsing issues. For example, @cash.app/$moegrammer.

The other benefit of this is that the inclusion of money address IDs is also a bit easier to read:

[!tip] IDs can be used as part of the DAP protocol to specify a payment address for a DID subject

For example: @didpay.me/moegrammer#munn

[mistermoe]

Great points @frankhinek! I think we should go with either @moegrammer/cash.app or @cash.app/moegrammer

Instinctively I lean towards the former because I imagine people will think about who they're sending to first.

Though given the wide use of @ on the web, I wonder if we'd run into weird rendering collisions. Let's see what GitHub does when I type in: @mistermoe/cash.app

[aparkersquare]

I'd independently raised the option of using the domain first with @mistermoe, but after considering again I agree that having the name of the person first seems more natural (matches the way I think about sending to a person, not where their ID lives). Apps can help with completion, but I'd guess not all apps are going to do a great job of that.

Considering what symbols are common on (US) keyboards and Android keypad, some options are @ / $ # &. The & and # end up blending into the name when you put as the separator (e.g. @moegrammer&cash.app). As noted above there are cultural issues with $, although I think that might still be acceptable.

Assuming a "prefix" and "separator" this gives us a short-list of

• @moegrammer@cash.app
• @moegrammer/cash.app
• @moegrammer$cash.app
• /moegrammer@cash.app
• /moegrammer/cash.app
• /moegrammer$cash.app
• $moegrammer@cash.app
• $moegrammer/cash.app
• $moegrammer$cash.app

Overall I like @moegrammer/cash.app

[aparkersquare]

Also worth noting it was a very good call to avoid DAPs looking like email addresses.

That scheme has been used for lightning address (and UMA), and this already causes issues.

For example when coinbase launched lightning, some people tried entering a lightning address instead of a lightning invoice. Coinbase treated it as an email, which they already supported as a "send to an email so the email owner can claim the bitcoin later" flow. This would be very bad for customers who might not own the email associated with the domain (e.g. CashApp customer have no access to \<cashtag>@cash.app email, and in fact someone else might own that!).

Best to avoid that issue entirely, and make DAP a separate scheme.

[mistermoe]

Great point @aparkersquare