Payy, a project from Polybase Labs (opens new window) — a team within Protocol Labs — recently launched the first non-custodial, privacy-preserving stablecoin Visa card. Designed for everyday use, Payy aims to make borderless money a reality, closing the long-standing usability gap for crypto in real-world transactions while putting privacy at the center of payments. On August 6, 2025, Protocol VC partner Lacey Wisdom (opens new window) spoke with Payy CEO and co-founder Sid Gandhi (opens new window) on a Protocol Labs X Space to dive into the launch. Gandhi shared lessons from launching in high-inflation markets like Argentina, explained the technical breakthroughs behind Payy’s zk-powered network, and outlined his vision for a truly global, self-custodial financial system. Note: This conversation has been edited and condensed.

Lacey Wisdom: Let's get started here. I'm Lacey, one of the partners at Protocol VC (opens new window) where we make early stage investments in companies at the cutting edge of blockchain tech and frontier technology, typically investing from pre-seed to Series A. And Sid is one of our amazing founders. He is the CEO of Payyy, and he's got an exciting new launch today. So Sid, I'll bring it over to you.

Sid Gandhi: Yeah. My name is Sid Gandhi, CEO, and co-founder of Polybase Labs. We built Payy and we just launched something really cool today, which is the Payy card. It's the first non-custodial stablecoin card with privacy. And I'll go a little bit more into why that's super important, but I'm just super happy to be here. We're also supported by Protocol Labs as an investor and have been part of the community and the network for a few years now. So thank you for that.

Lacey Wisdom: Let's back up a little bit. Stablecoin has become one of the biggest topics in crypto. Even some of my kind of normie, non-crypto friends have become aware of stablecoins. So Sid, I'd love it if you could just start by giving us a snapshot of why stablecoins are dominating conversations right now.

Sid Gandhi: I think the simplest way to think about it is we, humans, always try to find better technology and better ways to do things. And for the last, let's say three decades or so since we've had the internet, so much of our lives has moved to this digital-native world. Everything happens on the internet. And yet money is this weird thing that still has borders. We still talk about money based out of a certain country, right? So you have currency from the US or currency from the EU or other countries. It's about these borders and about these geographic locations around the world, and information in the world just doesn't work that way anymore. So I think the real reason why stablecoins are super important and are really popping off is because I think that realization is starting to hit more and more people that just like information, it makes no sense for money to have borders either. Now I won't say it's a completely useless thing to have borders around money. I think there's some use cases for it today, but the world is changing quickly into a way where I think there will be no use cases for that in the future.

Lacey Wisdom: Could you explain a bit more about how Payy, one of the first products from Polybase, is really making stablecoins usable in the real world. And why was there this kind of barrier to making stablecoins useful in the real world in the first place?

Sid Gandhi: To me, when I think about real world usage, I think about someone on the street or someone that you know that doesn't have context about crypto, doesn't have context about even how money might work today, when it's in a bank, or a fractional reserve, or when you send money in different countries — like someone that doesn't have that context. For them to be able to just pick up and use something that gives them value in their life. The whole reason we built Payy was because we saw all of these great narratives and wishful thinking — and even products and blockchains and protocols that people had shipped over the last 15, 20 years — and none of them felt like that. None of them felt as simple as, OK, I downloaded an app, and now I know exactly what to do. That's what the barrier for adoption was, right? It has to be as easy as WhatsApp. Like you download WhatsApp and you just start typing. You don't have to think about connecting to the internet or like choosing which protocol you're going to use or which encryption you're going to use.

Lacey Wisdom: Totally. And I remember, landing at the airport once in a different country and not getting cash out of the ATM there, like not doing an exchange and hopping into a cab, and then realizing I had no way to pay the cab driver. So the only way to pay them in a world without Payy or something similar was to actually leave an envelope of cash for 'em at my hotel front desk. But I remember thinking you were at the time just beginning to build Payy. And I remember thinking, “Wow, if I could have this driver just download the Payy app right now, we could exchange currency across our different currency types very seamlessly.” So I think it's really exciting.

Sid Gandhi: At a high level, the stablecoins that exist today weren't explicitly designed for payments. And what I mean by that is the initial value prop and use case for the stablecoins that we know of today — let's take USDC for example — really the first value prop that got product market fit for them was to be able to exit from non-stable or other token positions in DeFi for swaps — and essentially take profits, right? And that has nothing to do with payments. So you just leave that money onchain and then you swap in and out when you're trading. As DeFi grew around that, we had lending, borrowing, etc., and then we had stablecoin, real world adoption, mostly happening in other countries outside the US and Europe.

So think about Turkey — large stablecoin adoption. Some places in South America, specifically with the Tron blockchain, I would say, really had that on-the-ground adoption with USDT. That was interesting because even that wasn't explicitly for payments. It was for a stable store of value. And so if you look at the countries where that option actually happened, it's countries with really high inflation. I was in Argentina last year, like I mentioned, and stablecoins are not typically used for payments. They're typically used for taking your paycheck that you might be earning in pesos, for example, once a month; converting that into dollars USDC or USDT; and then being able to then convert back to pesos when you need it. And oftentimes you use a service or it's a money transfer person. It's not an unofficial business. And they just try to help you move money on and offchain with cash, right? So they were just not designed for payments. So the reason why that adoption didn't happen was because no one built an end-to-end product, as in from my paycheck to when I need to pay for my groceries — one product that can solve that use case. That's what we set out to build and the thinking around that singular end-to-end, simple to use case. Without that, we get this weird amalgamation of protocols and wallets and chains and weird things that we have today in crypto. We have to jump through a bunch of these hoops.

Lacey Wisdom: I think it's a couple interesting points there. One, I think you really hit the nail on the head here that so many of the DeFi products that we, being very crypto native, are used to interacting with, are really not for consumers. They're for prosumers: this other class of people who are used to trading and are looking to extract higher yield. And what Payy is really doing is building a consumer native product for the average person on the street to use. I think another interesting piece from that story about how in high inflation countries people are typically using and leveraging stablecoins is that there is still this critical component, this piece where they actually have to change the stablecoin into the currency itself. And that is also a point at which there can be some kind of issue. I've experienced this as well in Argentina, where in changing money into cash, you run the risk of getting fraudulent cash or not getting the exact exchange rate at the time. The Payy card launch today is really interesting because it's removing that requirement to basically do that transaction piece at the end point. Another piece that you haven't touched on though, which I'm really excited about, is privacy. A lot of things in crypto today are very public. But what's the risk of having every transaction be public, especially with payments?

Sid Gandhi: I personally think that it's absolutely crazy that we've accepted even the minimum amount of like payments happening today onchain being all public. What's the problem with that? First of all, when you start using stablecoins in the real world, that's a real physical location and time that you're tying a blockchain transaction to. And today, if you look at the other self-custodial cards, like right now, I can go on Dune. I can pull up the Gnosis Pay dashboard, and I can look at individual transactions, right when they're happening. If we are to scale beyond just a few users in crypto to the next hundred million, the next billion people, and actually improve and move humanity forward, that will not work. Privacy is a fundamental part of information. So we've had a ton of work in privacy over the last few years. With GDPR and stuff like that, I get it, like the cookie banners everyone hates, but at least they've brought the conversation into the spotlight of online privacy is important. My thesis — and our thesis at Payy — is that something very similar is going to happen in crypto when people realize how easy it is to analyze and exploit onchain transactions. Once you start hearing that companies like Meta or Google or others are starting to index and analyze those on chain transactions, there's gonna be a lot of people asking the big question of why are our financial lives fully public now?

Lacey Wisdom: A couple years ago we saw this rise of Social Fi, even in Web 2.0 with apps like Venmo, and then those apps quickly realized that consumers really wanted privacy, and so they integrated features to allow consumers to transact privately as well. That's why Payy is really differentiated from a lot of the solutions that are out there. So Sid, big news today, you're launching the Payy Visa card. What really makes this card different from anything else out there? You've already touched on that a little bit, but I would really love for you to hammer that point home.

Sid Gandhi: Two main things that make Payy card different than any other card that exists today. The first one, and this is the left curve, right? This is the “get everyone super hyped” is that it literally lights up when you tap. So I've been using my Payy card pretty much exclusively for all of my spending for the past three months while we've been testing it. You go to a restaurant or a bar and when you go to tap to pay, there's a Payy logo in the middle of the card. There's an OLED panel essentially embedded in the card, and it uses the energy from the NFC to light up the card, so there's no batteries or you don't have to recharge it and it literally glows when you tap. I kid you not, like the amount of people that have been completely shocked by that and immediately said, how do I get this? It has a pretty much 100 percent success rate there.

Lacey: Was that kind of like something that you were thinking about actively? Were you thinking about designing for a physical IRL experience when you were going through product design?

Sid Gandhi: Yeah, absolutely. I'll touch on the second unique point, and then I'll talk about why they work well together. So the second unique point about Payy card is it's the first ever self custody stablecoin card that has privacy. And so a lot of people have been asking on Twitter and stuff, and I've been responding, but just to clarify, what does privacy mean in this case? It means that your KYC data, that you have to verify your identity for any Visa card and for any kind of fiat interaction, right? So we've all done this probably a bunch of times already, and if you're in crypto and that's to run anti-money laundering checks and other fraud checks and stuff like that. That's fine. I think those are good and important things that keep people safe. They should be much easier and much better than they are today, and we're gonna work on that. But I think the thought process behind that is sound. The problem so far is that verification data, right? Your name, your ID, your address could be linked to your onchain address. For example in the MetaMask card, when you KYC, some party has that data, and that party also has your MetaMask address. Now on the surface, this doesn't seem that problematic, but when you plug your MetaMask address or your Ethereum address, let's say into ARCOM Labs or TRM or one of these blockchain analytics platforms, you would be surprised how much information you can learn about someone. You can look at times — so you can identify what time zone someone might be in. You can look at what protocols someone's interacted with, whether they have outstanding loans or deposits in particular DeFi protocols, how much money, total net worth that they have. So from one swipe of a non-private card, you can see the whole financial life of someone, if they're natively onchain.

We solved that by breaking the link between the KYC and the onchain transactions on Payy network. There’s a pretty deep technical explanation of how we do that with zk, and our docs are out there if you wanna read that. But those two things are what make us really unique, and to tie it all together when we're building this card. I personally wanted it to be really obvious that this was something truly new. In crypto and on crypto Twitter, it's very rare that we have something truly unique and truly new happen. As we all know, it's a lot of copy pasta. It's a lot of trying to shill things that might look interesting, but actually don't work or don't really do anything new. And so we knew we had to break through that noise. And so that's where the light-up aspect of the card came through.

Lacey Wisdom: That's incredible. And so with Payy, you're really delivering a card that truly gives users privacy for the first time ever, which is incredible. Without getting too technical, I would love to dig in a little bit more to why you decided to use zk and build your own kind of network instead of relying on existing chains.

Sid Gandhi: When we were originally starting to build Payy — just the payments part of Payy before the card even — we looked at trying to build it on top of a few different EVM chains. We looked at trying to build it on top of Solana. We looked at a few of the privacy projects that were in production and active at that time. And for one reason or another, none of them actually worked for what we wanted to achieve. Some of those reasons are block times. So some of the block times were way too long. We needed one second block times, at the maximum. We need payments to be essentially instant. We needed something that had configurable privacy. We needed something that supported stablecoins. Out of the box, we needed something that supported on and off ramps with USDC. And we needed something that works on phones. So a lot of the zk tech at that time, which was two years ago, and even today, actually just doesn't run efficiently on phones. It would take five minutes to generate a proof on your phone. We just said I guess we have to build all this from scratch. So we built our own zk circuits in Halo2, which is the same framework that Zcash has been using for many years and many other projects. We then built a payments network with our own in-house implementation of a Merkle tree-based state system. Then we built a verifier which verifies state changes and then posts proofs and hashes to a base layer. Then we integrated a bunch of on and off ramps and then we integrated the card. So the short answer is: literally there was no chain that you could build on at the time. Even now, I don't think there is a production-ready chain that supports the kind of attributes we want. So we built it, and that's called Payy network. And Payy network is where all the Payy card and Payy wallet transactions happen. The really exciting thing is we're gonna be opening up Payy network for other people to build on, probably by the end of the year. There's a bunch of people that want to build on it, and we have some design partners lined up, so I'm super excited about being able to open that up to others as well.

Lacey Wisdom: That's truly incredible, especially when you think about how much activity today is mobile. The fact that there wasn't a self-serve ready zk network that was also a mobile native that you could build this on. I think that Payy network is really gonna unlock so much potential for potential builders who are looking for private and private, very scalable and use cases that can also end up utilizing this as well. I know we've already touched on Argentina a little bit, but I would love to delve into what you've learned from launching in real world environments outside of the US.

Sid Gandhi: We've learned a lot. I grew up in the US, and you don't really have to think that hard about money in the sense that when you're domestic in the US, it's pretty easy to save your money safely in your bank account. Most of the time they don't blow up. It's easy to send money to people, to spend that money with cards and things like that. What I learned from my time outside the US in a few different countries was that all four pillars of consumer finance, which is saving, spending, investing, and borrowing, are actually quite difficult in other countries. And the tools that are available and the services that are available for finance are really not that great. A lot of people have adopted crypto in those places for saving which is the first pillar. But spending is still very early and I think we're really far away from at-scale investing using crypto, and then at-scale borrowing, our under-collateralized borrowing with crypto. The vision for us is to continue building until we can support all four of those financial pillars at a first-class level of support and infrastructure for everyone around the world.

Lacey: Were there any difficulties, especially since you have a real card, were there any issues with the physical component of launching, especially in an emerging market?

Sid Gandhi: Yeah, on the first part of it, Payy card is like when you apply for a Payy cardm and you get it today, right now, you'll get a virtual card, and you can add that virtual card to Apple Pay or Google Pay, so you can pay in stores and stuff. You can use the card number online. So in that way it's global. It's very easy for anyone anywhere to sign up and use in the supported countries. The physical card is interesting though, because there's not as many use cases anymore over the past couple years. To really need a physical card in most places that I've seen or that I've been to, like tap to pay, is quite well supported. Really, the physical card is kind of like the excitement and the interesting factor of it. I would say it's not really like adding a new feature set in a way.

Lacey Wisdom: If Payy becomes as easy and private as Payy envisions, how will that change the way that changes the way people think about money?

Sid Gandhi: I was speaking with Jeremy Aire from Circle the other day — they had an event at their offices here in New York — and I basically asked him this question. Look, USDC is much better than most currencies around the world. That's crazy, but in most ways it's better than all of these different domestic currencies that either have high inflation or untrustworthy financial systems or whatever. I was like, if the adoption continues right, and if USCC wins, what happens to all of these other currencies? His prediction was that we're gonna have a massive death of currencies, and there's gonna be less currencies in the world in 20 years or 50 years than there are today. At the time, that gave me goosebumps because that's a massive geopolitical prediction. And to circle back to your question, Lacey, I think what will happen is what has happened with the internet. Which is — you have a few platforms that through network effects just really dominate the infrastructure and improve people's lives. And, those platforms have a lot of power. What we're hoping is that we can design a monetary system where centralized companies don't have the kind of power that companies on the internet, like Google and Facebook, have. That's my prediction of what will happen, and what I hope will happen.

Lacey Wisdom: So a consolidation and currencies, that's interesting. And I think, there's some folks — without opening a can of worms — who have also had longer conversations around potential currency dominations and US dollar dominance versus Euro dominance. Going back to Payy, what is next for Payy after this Visa card launch? You've already teased opening up the Payy network, but curious what you're focused on in the next six months.

Sid Gandhi: Yeah, the Payy network conversation is there in the background, but from a consumer perspective, our next few priorities are to add in yield to Payy, so you start earning yield on your balance, and that's obviously going to be opt-in. We've gotten a lot of asks for Treasury Bill yield in Payy, so no commitment, but that is definitely the high priority thing we're looking at. Then we will expand the on- and off-ramping options, as well, around the same time. And what that basically means is being able to go in and out of Payy from different fiat currencies directly all around the world. Today we have Argentina as the first country where you can on ramp Argentinian pesos and Payy is actually the fastest, simplest, and easiest way to do that today. It's also the cheapest from the reports that I get, in terms of the spread for the foreign exchange transactions. And we’'ll be enabling US ramps soon. So that's ACH in the US. We're looking at adding SEPA in Europe, and then a bunch of other places around the world, as well. Essentially what that makes is a bank account that's fully onchain and fully self custodial. And my vision there is what we really see Payy becoming is the global bank account for everyone everywhere to be able to use financial services at the highest quality level.

Lacey Wisdom: And where can people go to follow along and try Payy for themselves?

Sid Gandhi: Payy_Link (opens new window) on Twitter [now X], of course. You can follow and DM me with any questions and things like that. Payy card is live, so you can get it right now. We've had a ton of people coming in today. If you want a light-up card, you have to collect a hundred thousand Payy points. It's not as hard as it sounds. You can either deposit funds and claim daily Payy points or invite people.

Lacey Wisdom: Really want to thank you for your time, Sid, and everyone at Protocol Labs for putting this together. We're really excited about the Payy card launch. Please get your Payy card, if it's of interest to you. And we'd also love for you to join us at LabWeek this year around Devconnect. It's going to be from November 13-19 in Buenos Aires. So come out and look for more information on that on our X account (opens new window). Thanks everyone.

Sid Gandhi: Thanks, Lacey. Thanks everyone. Bye.

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