Cashu is not an alternative to non-custodial Bitcoin. Nothing beats holding your own keys.

Cashu Ecash is for custodial systems that respect user privacy, have better censorship resistance, and allow half-offline peer-to-peer payments that are instant.

The days of corporate blockchains are over. They make no sense at all, they're centralized, and they are peak inefficient. Ecash beats all of that. It's fast, lightweight, and cheap. If you're running a service, you should consider integrating Ecash for your users.

There are already dozens (!!!) of mints out there, run by organizations, companies, or communities. Among these companies are custodians, wallet providers, LSPs, and online shops.

When will we see the first ecash in-game currency?

Cashu now has native mobile wallet apps, headless server wallets, web wallets that work in the browser, and wallets for social media clients. We have mint implementations in Rust, Python, Golang, and like 5 other languages.

We have tiny invisible wallets that live in web pages.

We're working on an authentication scheme that balances operator control and user privacy as best as possible. You can decide who can use your mint.

We have a dozen different open-source libraries and wallets that are improving every day.

It's all yours.

We're just getting started and the new year is going to be massive. After two years of crazy work on an entirely new protocol, things are starting to take shape.

We have a vision which is to bring Bitcoin to every corner of the internet. Ecash will bring us there.

Thank you everyone who believed in us, especially those who contribute to this project. Cashu has become a place where you can improve your coding skills, learn to collaborate, work on open-source, and do literal magic ✨ (cryptography).

Next year is going to be massive 🫡🥜

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Discussion

Can I find a material somewhere what cashu is and how it works?

of course! cashu.space > docs.cashu.space 🫡

We’re lucky to have you in the space Dr. Calle! Thank you and everyone else who’s working on this. Merry Christmas!

🫡 merry xmas sir!

same from me, Calle.

Amazing!

Preach! Onward & upward 🔥🧡

It's only the beginning

🔥

🔥🫡

What is the innovation in Cashu's development now that would make a difference and boost its adoption?

I have a HUGE problem with mints being custodial. there are people who will never ever see it as more than a toy while this continues to be the case. but I'll be charitable. there is a way to make a cashu mint more trustless by making it behave more like a ZK rollup. you'd need new opcodes though.

https://hackmd.io/@abdelhamid/cashu-starks

Running a mint is already quite easy and will be more in the future.

You'll have a family member or a close friend that will run one.

Because "who will build roads? :)

That doesn't improve privacy, it is quite the contrary when you force to report on the activities. Might as well go full KYC.

These mints are small business that facilitate the usage of anonymous payment coupons. For that goal they do their purpose just great.

Wouldn't use them for my off-grid purposes where internet is only optional but these kind of systems have been used for millennia, we are just watching its digitized version takes place.

it's not a report. it's a zero knowledge proof. the whole point of this method is you do whatever you need to do offchain, then you produce a ZK proof for what you did, then the chain validates the ZK proof. if the proof is invalid, the chain yoinks the money back.

you need a way to physically stop a "mint" or some other L2 payment appliance from stealing anyone's money. it's not enough to set up an attestation system and "catch" the naughty people after they already rugged. it has to be impossible for the mint to rug people. the people who are trying to convince you that we need to sacrifice trustlessness are wrong and you need to stop listening to them.

I don't mean a detailed report. It is reporting the mint activity level which is a dead giveaway of which ones to target first.

Don't get me wrong, I'm a monero fan so this type of proofs are expected but that is on a large blockchain. On a mint this would make it a target.

if you don't want to feel like you are standing on a big red bullseye then maybe you need an actually decentralized protocol that isn't cashu. it's like sheesh we had all the pieces of the puzzle already put together and then people completely forgot about it. cut the crap.

Cashu works as intended: give anonymous coupons to someone else.

It isn't for big sums of money. For that we already have proper anonymous crypto. It isn't to pay coffees and grocery, for that we already have zaps.

This fills a niche in the real world which isn't answered by other options. Even when the mint stops working, you won't see many people upset over it. In fact, the person running the mint is likely someone close to the customers and won't like to keep them unsatisfied for 90% of cases. It isn't perfect, but this is the real world. There are advantages to this loosen method that I think you are under-appreciating but that have a tremendous value to others.

I keep hearing the laundry list of what cashu "isn't for" followed by a ridiculous story about how everyone's mom is going to hold onto their allowance money for them and how that's such an amazing invention. do you even hear yourself right now?

It is a case for keeping it simple.

In either way, if you feel that strongly about a change then it might be a better approach to just implement a prototype and see how others react.

Interesting question.

For me onboarding pre-nostra people is key also for ecash adoption.

I've made the prototype I was talking about last month..

Feedback most welcome. Nothing about ecash YET.

https://github.com/ildella/noa

zapstore://tools.frankie.nostr.noa

>When will we see the first ecash in-game currency?

Not even close to what you're talking about, but I built an ecash "treasure hunt" prize into my "ahem, game" Wusang" Isle of Blaq.

https://peakd.com/bitcoin/@crrdlx/bitcoin-ecash-comes-to-wusang

thank you for your tireless work 👍🏼

Thank you Calle, awesome project. Lightning payments are so fast with Cashu. That surprised me. I thought they might be slow or fail sometimes, but no, paid several invoices and every one was basically instant. The UX has been great so far.

This is literally magic

Very useful! Thanks for this background 🧡 Merry Christmas!

All the very best of luck to you.

You rock.

Cashu is amazing.

I don't see lightning be used for very small payments in a bit so distant future. This things is the closest thing to actual cash in an actual wallet.

Analogies.

Cashu is everyday wallet + prepaid card.

Lighting is your bank account, for salary and larger expenses and recharge cashu.

Onchain bitcoin obviously is the store of wealth.

this scales!

Do you use cashu even for lighting payments? I’ve been wondering what kind of fees are when using it as a normal small lightning payments option

So far i have paid zero fees for zapping with ecash. And zero to transfers ecash between different wallet on the same mint.

I believe the future (present?) is zero fee bitcoin transactions with ecash.

Lnd only to refill. Maybe once a month or so.

Need to play more with it! Do you pay for anything outside mints? Like lightning invoices, or just strictly ecash?

How can I get started in cashu?

Install nostr:nprofile1qqstxwlea9ah3u6kjjszu6a7lrnhqkfh8eptp2z6v0e9558tlkkl2rgpz4mhxue69uhhyetvv9ujuerpd46hxtnfduhsz9mhwden5te0wfjkccte9ec8y6tdv9kzumn9wshszxnhwden5te0wfjkccte9ekkjmnfvf5hguewvdshx6p07xr4s5 mobile app or webapp https://wallet.cashu.me

They have a very simplemente setup and then they can receive a lightning payment to get some sats. Obviously start with small amounts, like 1K sats.

Thank you! Starting my ecash trip rn

Will you be paying by cash or card?

Experiment of the day, the QR code on that NFC tap card isn't sats, its a public key for my Cashu.mewallett. Meaning I can request locked ecash payments that only I can claim, even while I am offline. (P2PK).

Imagine walking into a store and paying for real things with paper ecash notes that you printed in your basement

And those notes are swapped in seconds for ecash at a different mint the shop owner trusts/owns

👀

Man I’ve been sleeping on this cashu shit I gotta read up.

Cashu is sexy (lmk if you have questions and I can maybe provide a 30IQ answer)

It makes sense to me that lightning becomes a decentralised version of ACH but for bigger payments or settling between bigger players (the future of interbank transfers).

While Cashu is used for all the day to day spending of everyday people.

Then on-chain is mostly for governments, rebels, wealthy folks, and banks.

Congratulations nostr:nprofile1qy2hwumn8ghj7erfw36x7tnsw43z7un9d3shjqpq2rv5lskctqxxs2c8rf2zlzc7xx3qpvzs3w4etgemauy9thegr43sa96tzn . In 2024, you have led a growing team of builders to incredible progress. I share and support your view that Cashu will play an essential part in linking more people to Bitcoin. I hear the critiques that remind everyone that Cashu is not Bitcoin and bears counterparty risk. In my view, this is an issue that wallets can solve. Wallets that will use heuristics (e.g., a beefed up version of https://audit.8333.space/) to transparently migrate tokens to more reliable mints, wallets that will push unreasonably large holdings out to permanent and non-custodial solutions.

I am looking forward to seeing the developments unfold in 2025. 🙏 👏

“When will we see the first ecash in-game currency? “ something I’ve been contemplating for a while.

Thought a perfect game would be an open source non Microsoft Minecraft Clone. Adding a real economic element to the game would open up some interesting possibilities.

Any news from Blockstream on cashu adoption?

Love it!

is ecash the same thing as XEC?

No I thought so to first time I heard about it. Search cashu instead

LFG

Congratulations and well done sir! I have heard about Cashu on a few podcasts and look forward to learning more and using it in 2025. Keep up the good work 🤜

An #ecash #vpn service would be cool.

Would be great.

I would also love to see some actual innovation in that space. The VPN model with one provider is so archaic. SPN is an interesting one

Have y’all seen nostr:npub13ue6qxwf23vjkw6lu6pkykx06q6tkvmwcgm2f7jtnkwjc42ahmyqwuxn33?

note1zngvn54laq4unhky6jrc48rs4gf08wt0tq3jgqz6mk05269lvjqq66qayp

I've been to BTC++ Berlin to learn more about it.

Bulk/reseller use case is obviously promising.

eCash based NWC (rather than only lightning) would be incredible for anon services

Integrated ecash payment with Mullvad or proton

which mint do you prefer?

cashuBo2Ftdmh0dHBzOi8vbWludC5jb2lub3MuaW9hdWNzYXRhdIGiYWlIAE963yoENWxhcISjYWEYgGFzeEAxMmU5YzJlYzBhMDVlODQ3MmFjMWRkYjU1NjIwZGI3ODhhODIyMWRjMTA3M2EyMzM0NzNjODhjMDE0N2ZkMTZkYWNYIQLhZ-cps3ysZ1qJw5ojZVOWCCkcyeVEnSGcuyQ9vICLnKNhYRhAYXN4QGQxZmM3MjA5MTIwNzVmMWRmYjlhZmY3NTQ2MzVlYTY1MzljMTZjZjEwNWVlMzQ5OWUwODYzODY0NTc5YTY5YzdhY1ghA2K0-hACAt3xaX7bf8mMnrChLOY6klGup9xWMv7q8TrOo2FhEGFzeEA1MGU3ZGQ3ZGFmOWY4MTI3YzM3YjllOTAwMGYyNWFiZDZkNzMyZGQyNTdmYjJhOGFmZDEyNWFkMzFlNmY3ZTMxYWNYIQN60-ubA0q2QGJjSdDFZnZ56sZrjk5fcPkOzdhK78B9IKNhYQJhc3hANjQyZWYxZDYyODQxN2NjN2Q3YzIxMWI4YWViNTNjNjU1Y2M1Mzg2N2UwMjg3MzMyMGYxYTY4MmQxOTcyOWE3Y2FjWCEDgijLcqV-bxj2GaatxxzHNDWP7xbA-HDsRWorcP34lPc

wow how on earth was I the first

Nice one Calle!

It sat there unclaimed for several hours! Proof that no one has built a bot yet to scour nostr for any unclaimed e-cash that’s lying around…

We’re so early!