 Okay, hello there, how is everyone? My name is Ossil Marchano, I'm a developer. And the mic, where is the mic? This one, okay. I'm a developer, a new taller. We are building a open source payment system. I want to talk about it, how it is built, what it is aiming. So, first I want you to know that this is a digital payment system, it's not a banking system. So I wanted to show you some examples of what does it mean. And it's a payment system that is token based. So what does it mean a payment system that is token based? So the wallet that the user is going to be installing will have the token like cash, like physical tokens. It's not going to have a reference account to a database. So in this way, it will be very faster and easier to pay to some merchants, because there is no third party involved. We are going to, I want to talk about the use case first to set up what we are going to talk. There you will see some differences with cryptocurrency. We are talking a little about them and why it's different just to keep in touch. Why it's different? And then we are jumping into the main components of Taller and how they interact to build up the system. And if you are looking enough, we are going to see some demos. I have some, I built something interesting here that I wanted to show you for this talk. So I want to hurry up, so we will have time for everything. So this is Alice. Alice likes building video games since she was a kid. She grew up and she built an arcade room and the good, the business is really good, but she has a problem. I'm coming from Argentina and Alice is from Argentina and Argentina has this problem with currency that is the inflation is very bad and the currency, the money has started to get low value. So she's not rich, but she's having problem with the cash. And she said, since she's a hacker and she always working with digital things, and she said, okay, maybe we can move into the digital world to try to solve this problem. Let's start to think what we can use. She knew about this conference, but she couldn't get in here. And she first things in credit card, but she has this issue that kids doesn't use credit card, not yet. Also in this case, credit card has this issue that has some fee that is really high relative to the cost of playing a game. So it's not possible for her. She also is thinking about this platform like all the platform that are already open. But most of them doesn't have open APIs like we saw in some talks. If she wants to iterate with some vendors because some of the people that are coming here have some account in a particular platform, she will need to iterate to a different platform and it will be a hard problem to solve. So another guy came, Bob, and she just had an idea. You need block change, she said. But yes, it may be a solution, but she started to think about the main block change, Bitcoin Ethereum. And for her particular problem, the transaction cost and transaction delayed, maybe it's an issue. Lightning network is promising. Building a new coin for this particular case seems like a bigger problem than the initial one. So she keeps investigating what is around. It's not a bad solution. I'm not saying it's not a bad solution, but there are alternatives. And she heard something about this guy, Richard. I don't know if you know about him, but in a conference, in a speaking, he mentioned a project called Newtaller that has this feature that is anonymous and private for the consumer, but not for the one who's selling and providing the services at the merchant. So she thought, okay, maybe it's nice and start investigating about this project. And she found that Taylor is much more closer to the cash than an account-based system. When you have an account-based system in the physical where you have a lecture, when you have a credit account and you move money from one place to another, and in the cash, you have something that you give to someone else to cancel some transaction. Moving this into the digital world, in the part of using tokens in the digital world, you have this problem of double-spending. So Taylor addressed this issue using a centralized exchange and some tokens that guarantee the customer that is not being traded by the exchange. The exchange cannot correlate the withdrawal with the deposit. So the exchange, whenever it gets out of the deposit, it doesn't know who is the money from. So the user gets private payments and with no traceability. A lot of people is talking about the democratic risk of using account-based system in government. So this is interesting. It's not part of what Isis is thinking right now because she wants to build an arcade room, but okay. Seems like a lot of people who's working on this. She also found nice documentation that you can check out. The documentation to build this is open source. It's not just open source, it's flow. So she as a hacker can build on top of this software, build solution for her. Talk to the community, read in the news. A lot of information there that you can also check out. And she read through these documentations in the key components of the system. And the key components are basically, I'm going to talk just a few of them because there are more. The exchange, the wallet, and the merchant. So a customer who wants to buy something using Tyler needs to install a wallet. There is a web extension to use the browser and a mobile extension. We are going to see them running. There is an exchange. This exchange, you need to think it as an interface of a banking system. So if I want to use cash, if I want to pay in the street, I go to an ATM, I get cash and use it in a merchant. This is the same but in the digital world. So the wallet is going to talk to the exchange to say, hey, I want to get a Tyler tokens. By the way, this Tyler token doesn't have a market value like a coin, a crypto coin. This Tyler tokens, if they are dollars, they are, you have $10, you have $10 in your wallet. It's not like an extra currency involved. So the exchange gives you the coins into the wallet. There's a withdrawal process. The exchange doesn't know who is getting the coins, doesn't have an account or information about the user who is getting the coins. And then the wallet is going to use these coins to sign tickets needed that the merchant needs to create to provide the services, to get paid. So after the wallet signed or paid the merchant, the merchant can use this information, this contract signed by the coin to say the exchange, hey, I want this money that I get because I was paid with your currency. You see the loop here and the exchange cannot relate who was the one that withdraw the money. Not even when it withdraw the money. So the user get the privacy that he needs. And the merchant needs to tell the exchange how money is getting. So this is really important to be taxable. So far so good? So, okay, yes? Taller is the exchange? Taller is the whole system, the whole protocol that interacts with the system. And what we are building is the protocol so every individual component can be created by different participants. So you can build a wallet that follow this protocol and to talk with different exchanges and different merchants. So we have a software reference that I'm going to show you right now, but someone else can build another wallet and use it with everything that I'm going to show you. The same for the exchange and the merchant. So after she saw this, she'll say, okay, show me the money, where's the demo? I want to see it running. So Phil, she saw a wallet goer station. I am going to show you right now. Yes, I can show it. She saw our extension. She, we draw money from our bank that we have in the demo, we have a bank because maybe this is a better way to show it. So when you fill a wallet, you need to talk to the exchange and the exchange is going to say, okay, you want $10 in Taller coins, you need to send me $10 in my bank account. So what we are going to see is that the customer is going to be at the bank account saying, I want to withdraw coins and the exchange is going to say, okay, send me your $10 to my account, I am going to print it for you and you are going to, I am going to give these coins to your wallet. With that, the customer can talk to the merchant and when the merchant say, you need to pay for this, the customer is going to use the wallet to sign the contract and the merchant is going to receive this signed contract and tell the exchange, I want to receive this money in my bank account. Yes, so this exchange is, services is like interface like the credit card because it's allowed you to pay, it's another payment system for different things. So if we can do this, let me see because I'm in another machine, let's try to do it. We can go to demo.taller.net, I don't know who is this computer, but I'm going to start the, install the, install the wallet and also you will see that it was not prepared, I was not prepared for this computer so, there you go, we have a good installation and as you see, I have no balance here, there is no money yet. I am going to go to the bank, demo.taller.net, I have already installed my wallet, I'm going to read and then at the bank, let's create a new user, all these, all these two, I think I'll read, there we go, never. So this bank is also a reference offer that another bank can build and this bank knows about Taller, so it has a button that said start withdrawal process with Taller. So the bank is going to show me a page without QR code to start the withdrawal process so when I start withdrawal process, you will see this QR code and my extension know that this page has this withdrawal so I'm going to withdraw money. Before doing the withdrawal process, I need to acknowledge the long, long, long thermal service and when I confirm, then I'm going, the wallet send me back to the bank because the bank need a confirmation step, they said, okay, you're going to send five kilos to the exchange, you see that? So seven times seven is 49, okay, yes. And there we go, the wallet have received the coins. The wallet doesn't know about the user, doesn't have any information about the user, the exchange doesn't have any information about the user, the bank knows that the user a way transfer to some account, the exchange account and we have already there the coins. So next I'm going to go to a shop. This shop has an iteration with Taller. It responds for two payment required when there is some article that needs payment. So the wallet knows about this, when it found 402, it redirects to the Taller unit that is in the header of the response and I can use Taller to pay this, like it is a credit card in my browser so when I pay this, first I go to a confirmation page so I'm in a secure environment to make the payment. You show me some information, as you can see there is also a fee involved, I'm going to talk a little about it. And when I do payment, I can see the article. The merchant that is in the bag is receiving the coins and he will talk to the exchange to get the deposit back. So another thing that I saw in this demo is the tipping feature. So the merchant can ask for payment but also can tip the user, given certain actions. So here what are we seeing is a question, what payment do you prefer? It doesn't matter the answer, but the thing is that when Alice answers this it can get a tip from the merchant. When Alice accepts this tip, okay you have the tip, I can see the balance here. I have a withdrawal, a payment, and a tip from the backend demo and this give me money that I can use in any other place. Yes, any other merchant. So effectively I'm getting money, like cash in my wallet. So going back to what is Alice doing, I'm going to show you this link to be... This is also dual with an Android device. We have an Android application. I want to show you something here. There is an Android you can search for taller wallet. So after seeing this Alice thought, okay, this is my software, but I want my arcade room using this, what I need to do. So, no, not that one, this one. So she thought about this using a cash validator connected to a computer to create a tip. So every time you use a cash validator, it will create a tip that a user can scan with the mobile device to get money to her or his wallet. And then using another QR code in a machine to do a payment. And since there is all the code there to be used and it is free software, she can start doing that and build the system. So after playing a little around, she came with this QR code. I will try to scan it right now, let me check. With the taller wallet. So since I have not yet filled with cash, the wallet doesn't do anything, but we can try to, let's go to the report. So as you can see, the money went through. So if I use another one, it won't validate. But if I scan it again, it's checking the tip. So this QR code is just that URL. I can use also the web extension to do the pickup. But what Tali's want to do is use the mobile phone. So every client there in the arcade room can use her mobile device. So you can see I'm getting 20 pesos from Argentina. I'm gonna set this tip. The information say also that this tipping is from the merchant. Now I have this balance in my wallet. And then what I can do is another QR code with the payment that every QR code might be different from different arcade machines. So when you pay, you need to review the payment and you can confirm and explain. So after she built this up, she thought, okay, this, oh no, this is not the machine. This seems like a good solution. And she tries and she's trying to build this right now in Argentina, doesn't matter. But this is it, this is Tali. And as you saw, there is no blockchain involved. Some services running in a server, all crypto technology. And it's mainly based on a paper from David Chom and black signatures. That's why the key, the token that the wallet gets cannot be correlated from the deposit to the withdrawal. So the user get privacy and anonymity. There is a lot of topics that we didn't talk here, but are really important. We just talk about the main features. There is auditors, that audit exchange. There is a coffee software that the merchant can use to create orders. Maybe I can show you. Because it's here when you see something running. Merchant. This merchant backend is the one being used by the credit arcade. So you will see the orders. For creating a tip, a tipping, you need to create a reserve that links in exchange. So you are going to say the exchange, I'm going to save this money. So user can pick up and you have an API to authorize this tipping. Let's change here. There is also nice other features that for example, age restriction coins. There are some coins that you can create. If you want, for example, to give coins to kids that cannot be spent in some products that are for 18 or greater. So this coin cannot be used with those products. It is a really cool protocol because the kid doesn't need to give any information about the age or who he is or who she is. It is in the coins. So the kids get these coins like parenting, for example. You, as a parent, you need to give the kid a special wallet or when you do the withdrawal process, you need to ask the exchange, okay, I want coins that cannot be spent in beer, for example. Every operation can have fees. So the exchange can operate and charge for the operation. There is a working process in the peer-to-peer payment because as I mentioned, you have the tokens in your wallet. But if you share this token with the other person, you need to trust the person who is receiving the coins need to trust that the coins are not going to be spent before you. So the peer-to-peer protocol, what allows is that you don't need to trust the other person who is giving you the coins. And of course, the wallet is like a physical wallet. If you lost the wallet, you lost the money. It's not an account with a reference to some places. So that's everything. If you want to know more, there are a lot of things. This slide is in my talk in schedule. So you can check for the links. You won't remember everything. This, everything, but the important thing here is that central banks are taking central banks and taking notice about this and talking about future implementation of digital money. And it's a really good project, really easy to jump in. I started working here almost two years from now. So please join. And that's it for me like this.