Bitcoin Forum

If you don't know what is it:
"Atomic swap is a smart contract technology that enables exchange of one cryptocurrency for another without using centralized intermediaries, such as exchanges."

I think atomic swap are a promising technology to do crypto-to-crypto trades.
Exchanges are shit because of many reasons: arbitrary fees, arbitrary rules, KYC/surprise KYC etc...
Direct exchange with other users is risky because of scammers. Yes, it's possible to use escrow but it's time-consuming and the escrow may request a fee.
If you do day-trading, exchanges will remain the best choice (because you don't have to pay txfee everytime), but if you do only a few trades occasionally, atomic swap would be a very good choice.

As far as i know, atomic swaps are not possible with every crypto. The 2 cryptos must be based on similar algorithms to have atomic swaps possible.
For example, litecoin to bitcoin should be possible.
As far as i know, there is no need to do soft/hard forks to allow the atomic swap, the're already possible.

The only problem is: how to do an atomic swap practically?
I did some researches and the situation is a little confusing. It seems there are some software but they seem crapware/centralized/not open source etc...also they act as a wallet. This isn't good, why should I trust new and closed-source wallets?
So the question is: is there some decent software to do atomic swaps? Even if it's only an experimental script or something similar, please post it there, so we can try to make a list of available software.

Personally, I don´t know any software which can be truly called atomic swaps.

I used services such as Shapeshift, Changelly, Instaswap etc for as long as I use crypto, but AFAIK they are not atomic swap software. THey are similar to exchanges.

Some of those services even use Binance accounts wallets (or other exchanges) to transfer those funds to your wallet.
i have noticed that, as sometimes those exchanges wallets are labeled in blockchain explorers.

I see many people calling those services Atomic Swaps, but I don´t think they are. Any thoughts on this?

Software for atomic swaps between hundreds of coins with different protocols and blockchains would be a maintenance headache. However in a specific case (https://bitcointalk.org/index.php?topic=5109561) atomic swaps could shine.

I understand that it would be nearly impossibile to make a software that can "swap" beetween hundreds of crypto.
But it would be very useful also a software that manages only the most "famous" crypto, for example btc, ltc, bch etc...

Really software are  atomic swaps between coins of blockchain..many softwares are working on blockchain   technology  and they are sucessful in their  field.

Yes they are atomic  Swaps.. because  they are doing good work..

Certainly that's not the reason, that's not even relevant to determine if those services are or not atomic swaps.

Bit they are not atomic swaps. I made a small research and atomic swaps cannot be centralized and must be done by smartcontracts written in the blockchain. Something like a dex.

I found some code for atomic swaps:

https://github.com/decred/atomicswap

It doesn't seem very user friendly to use and it's probably at an "experimental level" (it's better to not use it for huge amounts), but it's a starting point.

Agreed I think they are currently acting as gatekeepers keeping the potential for new project down. I think we will see swaps in the future.

I belief you can do atomic swaps using BlockNet (video (https://www.youtube.com/watch?v=d8q2VhWyhJQ), although it's easier to use now). The only disadvantage is you have to pay the 'broadcasting' fee in their coin.

no, they are not atomic swaps.

If Shapeshift or Changelly wanted to rob you, they could. That's not possible with real atomic swaps

Yes. I agree. I read about it and atomic swaps must be made through smartcontracts.
Do you know where can I find real atomic swaps?

only in non-production software, there are (AFAIK) no marketplaces with atomic swaps. Certainly no protocol has emerged from any developer in the space, so anyone claiming to be offering atomic swaps should be looked at very very carefully

Using lightning payment channels is often touted, but there was some doubt amongst developers whether it would be possible in a way that would stop traders gaming the system. I saw a recent mailng list post on lightning-dev that gave a hint that the problem may be resolvable.

tl;dr it's too soon for atomic swaps

There's ShapeShift, Changelly, Komodo and Rubix. Some wallets are non-custodial, meaning you control the keys and they can't steal your money. I recommend going with those. I'm not sure what it means if a wallet is both non-custodial and closed-source though. More on this topic here: https://www.forbes.com/sites/lukefitzpatrick/2019/09/02/a-complete-beginners-guide-to-atomic-swaps/#4c12b2c46178

no


no


no


...and no



there are not any atomic swap services in operation, "send us BTC to our address, then once we receive, we send you LTC" is NOT an atomic swap. Anyone who says so is either ignorant or lying

Okay thanks for clearing it up. How do these services work then if they're not atomic swaps?

they say "send us BTC to our address, then once we receive, we send you LTC"

that is not an atomic swap

What about AtomicDEX? https://atomicdex.io/  I've read a lot of positive feedback about it. I haven't tried doing swaps yet, I'll be trying it out soon.(Since it's in open beta now)

I seriously doubt it


To do an atomic swap, you need wallet software that writes a specific transaction script to make it happen. Unless that website is for such wallet software, then they're just using "DEX" and "atomic swap" for marketing purposes

and if so, they are lying. if the name of the website is a lie, you can't realistically expect that they won't lie about other things too

As was mentioned above by trucie months ago, Blocknet has 100% real atomic swaps on their Block DX exchange (requires full nodes in order to create and verify the transaction scripts you're referring to for now... a lite client is currently being developed though that'll leverage the XRouter network to do this vs full nodes).

For example, here are some links where you'll see the movement of funds to and from the p2sh addresses that are created as part of the atomic swap algorithm:

LTC (order maker) traded for BLOCK (order taker):

1.  Maker deposits LTC into p2sh https://chainz.cryptoid.info/ltc/tx.dws?36986143.htm (https://chainz.cryptoid.info/ltc/tx.dws?36986143.htm)
2.  Taker deposits BLOCK into p2sh https://chainz.cryptoid.info/block/tx.dws?2476278.htm (https://chainz.cryptoid.info/block/tx.dws?2476278.htm)
3.  Maker spends BLOCK from p2sh, sharing secret https://chainz.cryptoid.info/block/tx.dws?2476283.htm (https://chainz.cryptoid.info/block/tx.dws?2476283.htm)
4.  Taker spends LTC from p2sh with secret https://chainz.cryptoid.info/ltc/tx.dws?36986148.htm (https://chainz.cryptoid.info/ltc/tx.dws?36986148.htm)

Can confirm Blocknet is the real deal. No IOU's here and you trade direct from your own wallets where you control the private keys. Have traded there myself.

right, but you have to buy their token to use it.

if there's more than 1 transaction, it's not an atomic swap. Blocknet could sell you a bunch of their tokens, then give you no access to people to swap with.

You pay a fee to the service node who makes sure no duplicate utxo's exist with regards to your counterparty's collateral so that the decentralized orderbook isn't bloated and taken advantage of - the trade itself is strictly a P2P atomic swap and the fee transaction has absolutely nothing to do with the entire atomic swap process.  The fee is only charged to the order Taker too, so you don't need to have any BLOCK if you make orders, only if you take orders.

Your personal definition of an atomic swap is clearly wrong.

The entire exchange is completely decentralized so Blocknet itself can't do anything to block access to people to swap with.

if that was true, there'd be no reason for takers to buy a token to make it work


the point stands: you can buy your AtomicSwapCoin, and get nothing. That's not an atomic swap, lol

When I use the wallet, I just enter the amount I want to swap and it automatically does it. Does that mean it automatically sends to their address without me knowing?

He is saying that they require him to send Bitcoin and that when they receive it they will send the other currency. However, that is not how atomic swaps work. So he's right. Something doesn't add up.

I have created a list of software (https://bitcointalk.org/index.php?topic=5171728.msg52042585#msg52042585) from what I believe to be tools or services that use "real" atomic swaps. Yes, most of them are not very "usable" but they exist.

I have included also some semi-centralized services where an intermediary only acts in tasks like "order matching", like SparkSwap (which claims to use Lightning) and Swap.Online. If someone knows their code and can affirm that they're _not_ real atomic swap tools, a comment (better in my atomic swap list thread) is highly appreciated.

About Komodo's AtomicDEX I have my doubts (above all being a mobile-first/mobile-only service), but must look deeper into it to really be able to give an opinion. AFAIK, however, BarterDEX (the antecessor of AtomicDEX) was a real decentralized atomic swap tool without intermediary (each participant had to run a software) using TierNolan's swap model.

Edit: Looks like AtomicDEX is legit; it is based on a rewrite of the technology that powered BarterDEX (the Market Maker 2 command line script). This script is to be run on servers or PCs, the mobile app is a light wallet that simply connects to these "liquidity providers" and arranges swaps with them.