Everytime I zap someone vie Lightning from my wallet, it takes 5-10 seconds for the zap to settle and for everyone to see it happen on nostr.

Everytime, I think "this could've been an instant nutzap". "Tap, boom. Tap, boom. Zap zap zap. I would be zapping so much more."

The reason a nutzap is instant is obvious. At this point, I hope that everyone knows that a Cashu nutzap is just an instant transfer of an IOU from one user to another.

Let's step back and look at a pure Lightning zap on nostr for a second. We all know that the vast majority of Lightning zaps is effectively an exchange of one custodial IOU against another one as well. Most people use custodial wallets. So why is it still so slow? It's the Lightning settlement between the two custodians that often takes 5-10s to complete. Note, some users actually do run their own node, manage channels, run LNURL servers, etc. But they still get the same UX.

Here is an idea. Let's say a user doesn't want to use Cashu. Pure Lighting maxi which I think is great. I've been a Lightning dev for years before I started working on Cashu. This user could still be nutzapped and even remain fully self-sovereign if they run their own node.

What if the receiving user's Lightning wallet (custodial or non-custodial) was able to melt all nutzaps it receives by watching the nostr wallet ("nutsack") of its user? Either for every nutzap or whenever enough nuts are accumulated, the service could withdraw the nuts to the user's real Lightning wallet.

Effectively, this would improve the zap UX by showing everyone an instant zaps. The receiving user's custodian (or themselves) would have to run something like a nostr-cashu-wallet-watcher on a server to receive while being offline, but they have to run a Lightning node and LNURL and all that anyway (they already have a server).

Even without a server, normal nostr clients without true nutzap support could withdraw all nuts accumulated while they were offline back to their Lightning wallet everytime they come back online. The only real difference to a normal zap is that noe it's the receiver's job to settle via Lightning, not the zap sender's.

Nevertheless, zaps on permissionless social media like in nostr will never be completely trustless. They can't solve the sybil problem for instance. If you want, you can zap yourself an infinite amount of normal Lightning zaps on nostr without moving s single Satoshi. We faked zaps in the early days like crazy just to have fun.

But it actually turns out, all that doesn't really matter too much at all. First, people seem not to abuse the sybil issue. We had fun for a few weeks but then it got uninteresting There is not enough to gain, no algorithm to fool, no benefit of lying (at least not yet). Second, zaps are literally free money given to you from a random person. Why would someone rug you if they want to literally gift you money? It doesn't make much sense.