David Marcus is used to building big things. In 1996, at the age of 23, he founded a successful company and sold another for $240 million to eBay in 2011. Shortly after, he became president of Paypalhelping build the company into a payments giant before taking a leadership role at Facebook where he oversaw the growth of the highly successful Messenger app. Marcus is not the type of man who accepts failure. However, in recent years, this is what he has had to face.

In his last role at Facebook, Marcus led the Libra project, a hugely ambitious attempt to create a global cryptocurrency, linked to real-world currencies, within WhatsApp and the company’s other apps. The project sparked a fierce backlash from politicians and was ultimately rejected. Undaunted, Marcus then launched his own company called Lightspark in 2022, raise $175 million to promote the widespread adoption of Bitcoin. This too has been an uphill struggle.

This week, Marcus took the stage at a swanky Los Angeles hotel to announce a suite of new Lightspark products that he says will put Bitcoin at the center of global money transfers. Slender and handsome with gray hair, Marcus charmed the audience with his vision, but in a sign of the challenge that awaited him, he said he would work on it for the rest of his life. We don’t know if this will be enough.

Bitcoin as a neutral solution

As anyone who has used Venmo or Zelle can attest, transferring money to the United States is free and easy. The same is true in other countries. It’s a different story to send money across borders, which involves sending wire transfers, a tedious process that takes days, usually costs around $40 and is not available after hours opening of banks. The reasons for this are partly technological, but above all geopolitical.

“All (financial) networks are run by countries or by companies that are perceived as businesses,” Marcus said, referring to government-run payment networks like FedNow or India’s UPI, and large companies like MasterCard.

Political leaders are reluctant to rely on another country’s network for something as critical as payments, meaning there is no equivalent of Venmo across borders. The result is that it is expensive or impractical to send even small amounts of money between the United States and Mexico, or between Singapore and the Philippines – as millions of overseas workers can attest.

The solution to this problem, according to Marcus, is to turn to a neutral and decentralized monetary network: Bitcoin. His company Lightspark is trying to do this by creating software that allows anyone to use the Bitcoin network without incurring its infamous costs and slow processing times. The task proved tedious since Lightspark relies in part on an existing upgrade for Bitcoin called Lightning Network – a service considered even by crypto enthusiasts to be buggy and expensive.

On Thursday, Lightspark touted a series of upgrades that it said will overcome flaws in the Lightning Network and accelerate the adoption of Bitcoin in global money transfers. These upgrades include the ability to connect any wallet to the Lighting Network 24 hours a day and a layer 2 network (a blockchain sits on top of a main blockchain like Bitcoin or Ethereum) of its own called Spark.

Meanwhile, Marcus said a variety of well-known financial brands including Band, Coinbase and NuBank – are testing Lightspark’s tools.

For Marcus, this is all part of a future where people will easily send money across borders using a Venmo-style interface. In the background, the transaction will take place by converting a currency, for example the Brazilian real, to Bitcoin, and then converting it back to the transfer recipient’s local currency, such as US dollars. It also predicts that stablecoin transactions, which are quickly gain groundwill migrate to the Bitcoin network from blockchains like Ethereum and Tron.

Lightspark isn’t the only company trying cryptocurrency as a solution to cross-border payments. San Francisco-based Ripple has long touted XRP as a “bridge currency” to make these transfers more efficient.

Marcus says Bitcoin is the best solution because it is much larger and decentralized than XRP, and because banks can believe the Bitcoin network is durable enough to be around in 100 years.

If you build it, will they come?

Marcus’ vision of Bitcoin as an important, neutral intermediary at the center of global money transfers is intriguing and, in theory, it could work. The question is whether Lightspark can convince anyone to use it.

The Bitcoin-based money transfer plan relies on users having what is called a “Universal Money Address” or UMA which, similar to email, allows anyone to send or receive with that address. On Thursday, Lightspark announced a tool that allows those with a UMA to easily grant allowing third-party apps to integrate the In practice, this means that people will be able to link their UMA address – a gateway to the Bitcoin network – to their existing banking and personal finance apps.

However, so far no non-crypto companies in North America appear to have done so, and Lightspark has not provided any details on when it will do so. The company, however, said Brazilian neo-bank giant NuBank was using its services and highlighted that the appetite for payment alternatives was thriving in Latin America.

Lightspark declined to share figures such as the number of active users that would indicate whether the service is successful. He also provided no details on the amount of revenue generated, although Marcus said Fortune the company is growing rapidly and charges various businesses on a per transaction basis.

Meanwhile, a person close to Lightspark’s ambitions, who spoke on condition of anonymity, said they believed the company was simply too late. He pointed to the rapid adoption of existing stablecoin networks as a sign that Marcus’ Bitcoin solution, no matter how elegant, will struggle to replace what people are already using.

Marcus does not let such doubts discourage him. He says Lightspark has a lot of money, thanks in part to its purchase of a significant amount of Bitcoin two years ago as prices were crashing. He predicts that, now that much of the technical infrastructure is in place, the world will soon be ready to make Bitcoin the backbone of global finance.

This story was originally featured on Fortune.com