Interview: David Marcus, CEO and founder of Lightspark

“When the market realises that Bitcoin is the best neutral settlement asset, it will change Bitcoin forever”

This interview should have taken place years ago. For years, Michael Amar — one of David Marcus's close friends who organises the annual Paris Blockchain Week — has tried to make it happen, but scheduling conflicts and the simple flow of daily life never aligned.

The timing of this meeting, however, couldn't be better. Since the beginning of 2025, Lightspark — the bitcoin payment company that David Marcus founded — has been announcing significant developments. From banks in Brazil and India to fintechs like SoFi, ShakePay, and Revolut, companies across the world are lining up to use Lightspark's solution for moving money globally: Spark, a peer-to-peer network that uses Bitcoin invisibly to issue and transact real-world assets, most notably fiat currencies. In David Marcus's mind, Bitcoin is native Internet money, and Lightspark builds the "plumbing" to enable transactions in the cheapest and fastest way possible. An analogy often arises: Bitcoin and its Layer-2 network, Lightning, are to money what IP and TCP are to the Internet. The thing is, almost no one using the Internet today is aware they're using TCP/IP. More often than not, people don't even know these are the protocols enabling data transmission. And that's fine. To push the analogy further, with a nod to antiquity, it's nice to appreciate the aeroplane and the postman delivering your letter, but that's not what matters when you want your loved one to receive your beautiful prose.

Lightspark is betting on the same behaviour: people and entities want to send value at almost no cost and at the fastest pace possible — the underlying technology is a secondary, even tertiary consideration. That's what Spark aims to achieve: creating a global money network where, for instance, a Texan can easily send US dollars that will be converted to euros once in the hands of their Italian friends. It's already live in 65 countries, serving over 5 billion people, and to accelerate its growth, Lightspark is also expanding by acquiring strategic companies, such as the European MiCA-licensed payment company Striga.

This is brilliant, and hardly surprising from someone who has always focused on payments from his early days. He sold one of his mobile payment companies, Zong, to PayPal, which he then joined as vice president and manager of its Mobile Division. Afterwards, he joined Meta (formerly Facebook) to work on its peer-to-peer messaging platform and then on its now-defunct digital currency project. A stellar career for this French-American entrepreneur, punctual yet pressed for time, accessible yet focused.Between two meetings in a charming hotel of Lugano — the Italian-speaking Swiss city where Tether hosts its bitcoin conference, Plan B — David  received us to explain Lightspark. 

The Node: You started in telecommunications, which led you to PayPal and then Meta. Could you share with us what brought you ultimately to Bitcoin?

David Marcus: I've been in payments for a while, but stumbling upon Bitcoin was completely different. It started in 2009, the first time, when the whitepaper was published. As a geek, I was intrigued. And at that time, I completely dismissed it. I thought, "Okay, this thing is unusable. It's really hard to understand. I don't have time. It's kind of cute, but not sure."

Then in 2011, a very good friend of mine, Wences Casares, who's considered by many to be patient zero in Silicon Valley, couldn't stop talking about it and really roped me into it. It kind of forced me almost to spend time going down the rabbit hole. And I never left since then.

Lightspark is a company built on a Bitcoin secondary network: Lightning. Lightning has been under development for the past ten years, basically. What is the current state of Lightning?

We've built on Lightning, and we continue to invest in Lightning, but we're very focused on Spark now, which is the Bitcoin Layer 2 that we launched about six months ago. It's backward compatible with Lightning and enables stablecoins to be issued on top of Bitcoin for the first time. It enables real-world payments with Bitcoin and stablecoins for the first time.

We still support Lightning for institutional connectivity into Bitcoin for real-time Bitcoin settlement because we believe that Lightning is great for the custodial use case. But for self-custody wallets and developer builder experiences that are permissionless, it really doesn't work well. With Spark, we've unlocked a tremendous amount of builder energy back into Bitcoin. That's what we're focused on right now.

What is the business model for Lightspark?

Lightspark is a global money movement company that enables global money movement for lots of banks and financial services and also developers that are building on top of Spark. We monetise by charging small transaction fees when people use our tools to send and receive transactions on the network.

You're funded notably by Andreessen Horowitz and Paradigm. Most of the VC money in crypto usually goes into altcoins. Was it challenging to find believers in Lightspark?

If you don't have a token and you don't create money out of thin air that you can actually throw around to incentivise people to build on your platform, you're forced to solve real-world problems. And I think that's the greatest thing, right? Because for us to get adoption, we need to be a better alternative to all of the other solutions to move money around the world. And that's a very high bar.

I can't throw millions here, millions there to actually get people to adopt our technology and our solutions. It really has to solve a problem. And I think that's great because enduring companies actually build something that has a job to be done for a certain constituency.

We have US banks that are on the network, we have banks in Brazil, we have banks in Europe, we have banks in Latin America. We're in Asia, and now we're launching also in Africa with a number of different partners. So it shows that you can actually use real-time invisible Bitcoin settlement to move any type of currency cross-border in real time, 24/7, at a very low cost. It kind of forced us to actually go in and do all of the hard work of building a real product.

“When you send an email, you don't think about SMTP or TCP/IP, the same way that when you send money through SoFi right now in the US to go to Mexico, you don't think about Bitcoin”

Those who used to pay with Bitcoin often regret it. Do you agree that it's going to stay complicated to convince people to pay with Bitcoin?

I think it depends. The way that I see the evolution of Bitcoin coming into everyday mainstream payments is at first as invisible infrastructure. Very good infrastructure, very good technologies become invisible. When you send an email, you don't think about SMTP or TCP/IP, the same way that when you send money through SoFi right now in the US to go to Mexico, you don't think about Bitcoin, Lightning, or Spark. This is the way that you build the usability of Bitcoin in everyday payments.

Then the question is: are you going to use actual bitcoin as a unit of account? I think gradually we're going to see that because you're going to start paying rewards in Bitcoin — small amounts of rewards in Spark wallets — get people to have a very tiny balance of Bitcoin starting to care about that balance. And if you make spending your bitcoin in retail actually very seamless, you're going to start wanting to spend a little bit of Bitcoin here and there. In certain parts of the world, it's going to be the way that you do things.

Alternatively, if you think about what I call "thin banking", which is basically no lending but just a wallet that holds USDT as checking and then bitcoin as savings—you're going to start being exposed to the two assets and you're going to be able to move freely between one asset to the other, depending on the use case that you're confronted with. So I think it's a little bit of both.

You are a true Bitcoiner and, as such, attached to decentralisation. Spark being a corporate Layer 2, how do you manage to maintain this decentralisation structure?

First of all, I take offence that it's a corporate layer! It's a Layer 2 that was invented by a company. But it's open source, and it's a permissionless network. We're not arbiters of anything that's happening on the network. If you want to build a wallet and issue tokens on top of Spark right now, you don't have to call me and sign a contract with me. You can go and build, which is the best thing ever, by the way. So it's not Base. It's a different world. It's not like any of these corp chains that aim to be fully centralised.

The other thing that Spark has, which is a unique feature, is it has unilateral exits to Bitcoin Layer 1. Meaning if you have a balance of bitcoin or stablecoin on Spark, and you don't want to ask for anyone's permission — any of the Spark operators of the Spark network—to actually collect your funds on Bitcoin, you can do it and no one can stop you.

So it confers the same level of trustlessness, almost, as Bitcoin Layer 1, with all of the utility of real-time cheap bitcoin and stablecoin movement on top of Bitcoin. We think we've hit the perfect sweet spot between utility and trustlessness. We still have a lot of work to do to make it better and to increase the capabilities of the network. But we don't consider it to be a corp-controlled thing because of all of this.

Lightspark acquired Striga. Why does it matter for Lightspark's growth?

Striga gives us access to the SEPA payment system in Europe — 32 European countries. That's very important for us because we're onboarding a lot of banks, and we need to provide services where the banks can actually connect onto the network, and businesses as well can connect onto the network without touching Bitcoin.

If I have SEPA Instant in Europe and I have RTP and FedNow in the US, now I can actually send money from Europe to the US in real time using bitcoin without me ever touching bitcoin. Connecting into the real-time payment systems of everywhere—basically everywhere they exist—is really critical. And Striga enables us to do that in Europe.

Revolut announced that it would use a Lightspark solution. How big is it for you and how do you think it will change the fintech landscape?

I think it's really important for us to have as many of these digital-forward banks coming onto the network because when you have more of them, you create more of a network effect, and then you get the next ones and the next one and the next one. Having the Nubanks and the Revoluts and the SoFis of this world being on the network is really important.

It's also important for us to prove that we can serve regulated businesses and banks and give them the tools for compliance that are absolutely non-negotiable if you want to send and receive transactions on a network. I think we've proven we can do that in Europe, in Latin America, in the US, in all kinds of different parts of the world. And I think that's a major breakthrough for Bitcoin, especially when you think about unlocking the utility phase of Bitcoin.

I asked you about Lightning Network, but what do you think about the current state of Bitcoin?

The first thing I think is really important is that everyone who's building on Bitcoin and has the means to support open-source bitcoin developer efforts should do so, because having more Bitcoin Core developers is going to help us maintain the protocol, maintain the network, continue to secure the network.

I don't want to get into the debates because you can never win an argument with anyone on anything, especially with hardcore Bitcoiners. So I'm going to let people who are very close to the debate figure it out. And I have faith in the incentive systems that Satoshi built into Bitcoin. And that ultimately, over the long run, all of these little disputes will get resolved and the best will come. I'm an optimist, and I think it'll be fine.

Still, do you think that Bitcoin's model is threatened by the fact that nowadays, especially in the West, people see it as a store of value?

No, I think it's a prerequisite step for it to become a true utility for everyday payments. Because if you don't have a massive value, you don't have financial institutions that actually care about using bitcoin.

JPMorgan just announced today that they were going to allow people to use Bitcoin as collateral for mortgages, which is like an insane thing to think about, even a year ago. You have SoFi that's using us to actually move money cross-border for millions of customers using Bitcoin, which also would have been crazy to say a year ago.

All of this is because there's appreciation of Bitcoin, the asset, that as an incentive drives institutions and people to care about the asset. If the asset doesn't have the liquidity that is required with all of the fiat currencies and all of the in and outflows, then you can't make it the best neutral open settlement asset for global payments. So it's a prerequisite.

How do you see Lightspark, let's say, in 5 or 10 years?

The way we see ourselves is basically a company that builds technologies and capabilities that enable all kinds of different businesses, banks, and developers to build really compelling money movement applications on top of Bitcoin.

Hopefully, we are basically going to create all kinds of new ways to move money around the world, and we're going to be at the centre of it. We'll have a lot of competition because everything that we've done is open sourced. I think that's the way that we want it to be because we don't want to be the fat throat to choke—otherwise there's no point of building on top of Bitcoin.

I think Bitcoin should be the open internet for money that moves trillions of dollars a day of transactions. And if we can help make that happen with many others and the community and the industry, then I think we would be very happy.

Do you think that Libra or Diem [Meta’s defunct project of digital currency] could exist with the current state of the regulation in the US?

I get a lot of questions about this, and I think, could it launch? Yes. Could it survive? No.

Someone said this to me yesterday, actually, and it's stuck with me. They said when you announced it, it was instantly systemic to all of the regulators, the central bankers, everyone, without even launching.

The reality is, if you're doing that now and you're becoming slowly but surely systemic and you're a corp chain, and so you have a centralised stablecoin on top of a corp chain, and now you're intermediating, say, 30% of the in and outflows of payments to Europe—do you think that the ECB will kill it? Yes they can. One phone call, done.

That's why it's important to build on top of Bitcoin. Because Bitcoin is unassailable. There's no one to call. It's harder to build on Bitcoin than to build a private corp chain. But at the end of the day, that's what's going to be around in 100 years.

So would you say that it is for the best if it didn’t work?

Yes. As hard as it is to say it, yes.

Some of your former colleagues from Meta moved on to altcoins (Aptos, Sui). Have you ever been attracted to this altcoins landscape?

Look, I'm probably a couple of billions of dollars poorer because I haven't, but I'm a product guy, and I just want to build things that solve real-world problems.

I think that the problem with the approach of issuing tokens is that it's a very distracting thing for teams. It gives for a period of time at least an illusion of product-market fit when you don't have it. And so you stop working on product-market fit and on doing the hard things to actually solve real problems.

I guess I like the hard way, and the hard path. So for me, it's building on Bitcoin and our token is bitcoin, and I think this is the way.

What do you think of the current state of crypto, Bitcoin excluded?

I'm really impressed. Outside of Bitcoin, when I look at the execution of the different players, I'm really impressed with what Solana has been able to do over the years. They've built a very high-performance Layer 1 and they continue to execute really, really well. I think for certain applications, Solana will be a better place than Bitcoin.

I think at the end of the day, Bitcoin is meant to be the money network. So for all things money, I think Bitcoin is going to be it. But there's so many other things to build. There's lots of interesting things: Base, if you're into an EVM chain, is really executing well as well. So there's lots of interesting things happening. But I'm a payments guy. I'm a money guy, so I'm on Bitcoin.

Do you see right now any systemic risk for Bitcoin?

There's always systemic risks. But I've been in Bitcoin since 2011, right? So it's been a while and everyone has a point of view on what is going to be the thing that's going to kill Bitcoin.

At first it was, "Oh, it's a thing used by all the drug dealers and the criminals and it should be shut down." Turns out that 99% of the financial crime is happening on traditional financial rails, not Bitcoin. You'd be a dumb criminal to use Bitcoin for financial crime. So that was squashed.

Then it was "It's going to use all of the energy in the world in a really bad way. It's bad for the environment. You should shut it down." Turns out actually Bitcoin has the best incentive system to accelerate renewable energy. Failed again.

Now it's like "Quantum is going to break bitcoin." Quantum… It's unclear when it's going to happen. It could happen tomorrow or never. It's unclear when it's actually going to be able to break the pre-quantum cryptography. But I think we're pragmatic people and the core development team are pragmatic people. There are good ways — except for the old keys — there are really good ways to actually evolve the cryptography of Bitcoin to be post-quantum resistant. And so it'll sort itself out.

I'm not saying there won't be bumps on the road, corrections, all kinds of different things that people are going to freak out about. But in the long run, we'll be fine.

Self-custody or ETF?

Definitely self-custody for me. I mean, you should own your bitcoin. But there's a range, right? Do you have your Bitcoin? Do you custody with a provider? Or do you have an ETF? Or do you have a share of a treasury company? You have all kinds of different ways to hold Bitcoin.

Personally, I think the best way to do it is a combination of custodial services by trusted entities and self-custody.

What do you envision for Bitcoin in the future?

I think that the utility phase of Bitcoin is going to kick in high gear very, very quickly—much faster than people have assigned hopes for. And I think that's going to completely change the game.

The minute that the market realises that Bitcoin is actually the best neutral settlement asset and network to move all the money in the world, and you start to see proof of that at scale, it's going to change Bitcoin forever. It's going to fulfil the original desire of Satoshi to make it a peer-to-peer payment system. And even if it's a few hops away from peer-to-peer, gradually the peer-to-peer volume is also going to ramp up. So I think we're going to be off to the races.