But why layer 3? What was wrong with L2?
In case anyone is still confused about nuts or what it means and why we always talk about it (me today haha), here is my know-nothing dummy explanation and why this is a big deal IMO:
Cashu is an ecash protocol(is this correct?) created by nostr:npub12rv5lskctqxxs2c8rf2zlzc7xx3qpvzs3w4etgemauy9thegr43sf485vg
People are calling them nuts because cashews are nuts... get it?
The terminology is irrelevant. They can be called tokens, air, water, chicken teriyaki.. it really doesn't matter! What matter is that this is a Layer 3 payment system that transfers tokens at the speed of light (or so I think). Lightning being layer 2, and bitcoin being layer 1.
The reason why this is a significant development is because now everyone has a cashu address. Thanks to amazing work by the legendary nostr:npub1mhcr4j594hsrnen594d7700n2t03n8gdx83zhxzculk6sh9nhwlq7uc226 , if you go to npub.cash you can see that you already have an address to receive these layer 3 tokens, which just happen to be easily redeemable into lightning. This means that any new person who joins nostr automatically has (custodial) layer 3 payment access, which can swap into layer 2 and into layer 1 and into fiat if need be.
I don't know any of the underlying mechanics of this, I am not a genius like nostr:npub12rv5lskctqxxs2c8rf2zlzc7xx3qpvzs3w4etgemauy9thegr43sf485vg and what I have described could be incorrect, but it sure feels like this is roughly how things work.
Nuts are custodial, meaning a mint is holding your balance and can look up your npub to see if you have some. Once called upon, these nuts can be sent to another nutter (cashu wallet) or directly to a lightning address! This interoperability makes everyone a layer 2 user. All we need is a clever UX toggle / button / terminology to make it really obvious.
IF this were to be turned into a library that devs could include in their client code and "it just works", THEN it could be a game changer! No more directing people on how to get a wallet right as they join. They can experience the magic of bitcoin indirectly via layer 3 > layer 2 transfer all without knowing anything (as long as they can get on nostr).
In practice, this means anyone joining an audio nest, a zapstream, a flare.pub can automatically get paid. Yes, it's just tokens, and yes it's centralized and custodial, BUT, they see the value instantly and are only a click away from digging deeper. It's a STEPPING STONE that makes it significantly easier to get onboarded into the new paradigm.
I have not been this excited since the discovery of nostr itself! If I'm mistaken somehow, or don't understand things correctly, please let me know and forgive my dumbass 🤣 And if this means what I think it means, then let's make magic happen!
Discussion
I believe you can have similar functionality with LNBits if i'm not mistaken. But then you have to go to lnbits to log in and try to figure out how to manage that.
If you could integrate with a nostr client, perhaps it would work? 🤷♂️
Every layer makes trade-offs. L2 solved a scalability issue with L1, but it still has issues - From privacy issues, to fees (even if low), to the need to be online 24/7. L3 makes certain trade-offs but manages to further solve some of these by offering pretty much perfect privacy, a PoC for offline usage and actually zero fees.
Just like we needed MACs and IPs on seperate layers, what ecash brings cannot be done inherently on L2.
The end goal, much like the Internet, and is what @Karnage was getting at, is that the user won't even know what layer they're interfacing with because the UI/UX abstracts it all.
More cool toys to play with?