Early on the morning of June 1, 2022, Alex Karp, the CEO of the data-analytics firm Palantir Technologies, crossed the border between Poland and Ukraine on foot, with five colleagues in tow. A pair of beaten-up Toyota Land Cruisers awaited on the other side. Chauffeured by armed guards, they sped down empty highways toward Kyiv, past bombed-out buildings, bridges damaged by artillery, the remnants of burned trucks.

They arrived in the capital before the wartime curfew. The next day, Karp was escorted into the fortified bunker of the presidential palace, becoming the first leader of a major Western company to meet with Ukrainian President Volodymyr Zelensky since Russia’s invasion three months earlier. Over a round of espressos, Karp told Zelensky that he was ready to open an office in Kyiv and deploy Palantir’s data and artificial-intelligence software to support Ukraine’s defense. Karp believed they could team up “in ways that allow David to beat a modern-day Goliath.”

In the stratosphere of top tech CEOs, Karp is an unusual figure. At 56, he is a lanky tai chi aficionado with a cloud of wiry gray curls that gives him the air of an eccentric scientist. He has a Ph.D. in philosophy from a German university, where he studied under the famous social theorist Jürgen Habermas, and a law degree from Stanford, where he became friends with the controversial venture capitalist and Palantir co-founder Peter Thiel. After Palantir became tech’s most secretive unicorn, Karp moved the company to Denver to escape Silicon Valley’s “monoculture,” though he typically works out of a barn in New Hampshire when he’s not traveling.

The Ukrainians weren’t sure what to think of the man making grandiose promises across the ornate wooden table. But they were familiar with the company’s reputation, recalls Mykhailo Fedorov, Ukraine’s Minister of Digital Transformation, who was in that first meeting. Named after the mystical seeing stones in The Lord of the Rings, Palantir sells the same aura of omniscience. Seeded in part by an investment from the CIA’s venture-capital arm, it built its business providing data-analytics software to U.S. Immigration and Customs Enforcement (ICE), the FBI, the Department of Defense, and a host of foreign-intelligence agencies. “They are the AI arms dealer of the 21st century,” says Jacob Helberg, a national-security expert who serves as an outside-policy adviser to Karp. In Ukraine, Karp tells me, he saw the opportunity to fulfill Palantir’s mission to “defend the West” and to “scare the f-ck out of our enemies.”

Ukraine saw an opportunity too. At first it was driven by desperation, says Fedorov, 33. With the Russians threatening to topple Zelensky’s democratically elected government and occupy the country, Kyiv needed all the help it could get. But soon, government officials realized they had a chance to develop the country’s own tech sector. From European capitals to Silicon Valley, Fedorov and his deputies began marketing the battlefields of Ukraine as laboratories for the latest military technologies. “Our big mission is to make Ukraine the world’s tech R&D lab,” Fedorov says.

The progress has been striking. In the year and a half since Karp’s initial meeting with Zelensky, Palantir has embedded itself in the day-to-day work of a wartime foreign government in an unprecedented way. More than half a dozen Ukrainian agencies, including its Ministries of Defense, Economy, and Education, are using the company’s products. Palantir’s software, which uses AI to analyze satellite imagery, open-source data, drone footage, and reports from the ground to present commanders with military options, is “responsible for most of the targeting in Ukraine,” according to Karp. Ukrainian officials told me they are using the company’s data analytics for projects that go far beyond battlefield intelligence, including collecting evidence of war crimes, clearing land mines, resettling displaced refugees, and rooting out corruption. Palantir was so keen to showcase its capabilities that it provided them to Ukraine free of charge.

It is far from the only tech company assisting the Ukrainian war effort. Giants like Microsoft, Amazon, Google, and Starlink have worked to protect Ukraine from Russian cyberattacks, migrate critical government data to the cloud, and keep the country connected, committing hundreds of millions of dollars to the nation’s defense. The controversial U.S. facial-recognition company Clearview AI has provided its tools to more than 1,500 Ukrainian officials, who have used it to identify more than 230,000 Russians on their soil as well as Ukrainian collaborators. Smaller American and European companies, many focused on autonomous drones, have set up shop in Kyiv too, leading young Ukrainians to dub some of the city’s crowded co-working spaces “Mil-Tech Valley."

War has always driven innovation, from the crossbow to the internet, and in the modern era private industry has made key contributions to breakthroughs like the atom bomb. But the collaboration between foreign tech companies and the Ukrainian armed forces, who say they have a software engineer deployed with each battalion, is driving a new kind of experimentation in military AI. The result is an acceleration of “the most significant fundamental change in the character of war ever recorded in history,” General Mark Milley, former Chairman of the Joint Chiefs of Staff, told reporters in Washington last year.

It can be hard to see that from afar. By all accounts, the war in Ukraine has settled into a stalemate, with both sides hammering away with 20th century weapons like artillery and tanks. Some view the claims of high-tech breakthroughs with skepticism, arguing that the grinding war of attrition is little affected by the deployment of AI tools. But Ukraine and its private-sector allies say they are playing a longer game: creating a war lab for the future. Ukraine “is the best test ground for all the newest tech,” Fedorov says, “because here you can test them in real-life conditions.” Says Karp: “There are things that we can do on the battlefield that we could not do in a domestic context.”

If the future of warfare is being beta tested on the ground in Ukraine, the results will have global ramifications. In conflicts waged with software and AI, where more military decisions are likely to be handed off to algorithms, tech companies stand to wield outsize power as independent actors. The ones willing to move fast and flout legal, ethical, or regulatory norms could make the biggest breakthroughs. National-­security officials and experts warn these new tools risk falling into the hands of adversaries. “The prospects for proliferation are crazy,” says Rita Konaev of Georgetown’s Center for Security and Emerging Technology. “Most companies operating in Ukraine right now say they align with U.S. national-security goals—but what happens when they don’t? What happens the day after?”

In the months since Karp’s cloak-and-dagger first meeting with Zelensky, Palantir brass have fallen into a familiar routine on their frequent trips into Ukraine. In October, I met a London-based Palantir employee at the airport in Krakow, Poland. We were picked up in two armored cars, handed emergency medical kits “just in case,” and driven to the border with Ukraine. Gone was what one executive described to me as the “Kalashnikov-between-the-knees vibe.” We zipped through the border checkpoint, where young Ukrainian recruits dozed in the light rain. After dozens of these journeys, Palantir employees have their favorite gas-station snacks on the long road to Kyiv; their favorite drivers (a hulking former soldier for the Polish special forces who goes by Horse got us there with terrifying speed); and their favorite specialty coffee shops around the capital. These days, the lobbies of Kyiv’s five-star hotels are full of security details trying to inconspicuously sip beers while waiting for foreign-defense, tech, and government executives.

Much of Palantir’s work there is conducted in stylish co-working spaces by a team of fewer than a dozen local employees who work directly with Ukrainian officials. “It often feels like a tech-startup vibe: let’s see what we can do with two old cameras and a drone flying around,” says Vic, an engineer who left their job at a U.S. tech giant to work for Palantir in Kyiv after the invasion, and asked to be identified by a pseudonym for security reasons. “Except we’re in the middle of a war."

With a few clicks, a Ukrainian Palantir engineer showed me how they could mine a dizzying array of battlefield data that, until recently, would have taken hundreds of humans to analyze. Palantir’s software processes raw intelligence from sources including drones, satellites, and Ukrainians on the ground, as well as radar that can see through clouds and thermal images that can detect troop movements and artillery fire. AI-enabled models can then present military officials with the most effective options to target and enemy positions. The models learn and improve with each strike, according to Palantir.

When the company first started working with the Ukrainian government in the summer of 2022, “it was just a question of pure survival,” says Louis Mosley, Palantir’s executive vice president for U.K. and Europe. Palantir hired Ukrainian engineers who could adapt its software for the war effort, while also serving as interlocutors between the tech company and Ukraine’s sclerotic bureaucracy. Government officials were trained to use a Palantir tool called MetaConstellation, which uses commercial data, including satellite imagery, to give a near real-time picture of a given battle space. Palantir’s software integrates that information with commercial and classified government data, including from allies, which allows military officials to communicate enemy positions to commanders on the ground or decide to strike a target. This is part of what Karp calls a digital “kill chain.”

Although recent earnings data from the company indicates that partner countries have chipped in tens of millions to offset Palantir’s investment, Ukraine has not paid Palantir for its tools and services. The company's motivations in Ukraine have little to do with short-term profit. In recent years, Palantir has sought to shed its reputation as a shadowy data-mining spy contractor as it expands its list of commercial clients. Its tools have played a role in uncovering the financial fraud carried out by Bernie Madoff, rooting out Chinese spyware installed on the Dalai Lama’s computer, and allegedly aiding in the hunt for Osama bin Laden—a long-standing rumor the company has been careful not to dispute. More recently it has highlighted its work with the U.N. World Food Programme and the use of its software to track COVID-19 vaccine production and distribution.

Karp has long dismissed widespread criticism that Palantir’s tools enable intrusive government surveillance. Amnesty International has accused the company of seeking to “deflect and minimize its responsibility to protect human rights,” and said Palantir’s tools have allowed government agencies to track and identify migrants and asylum seekers to carry out arrests and workplace raids. The CEO says he sees a moral imperative to supply Western governments with the best emerging technology, calling for “more intimate collaboration between the state and the technology sector” that he believes will allow the West to maintain its edge over global adversaries.

In Ukraine, Palantir had found an opportunity to put this mission into practice while burnishing its reputation. “People often have preconceived notions about Palantir, but our products work,” says vice president Josh Harris. “When it’s existential, and when it needs to work, you take off your ­blinders, you take out all the politics.” And in Ukraine’s leaders, the company found a group of young, tech-savvy officials who could help them with more than just PR.

Ukraine’s use of tools provided by companies like Palantir and Clearview also raises complicated questions about when and how invasive technology should be used in wartime, as well as how far privacy rights should extend. Clearview CEO Ton-That contends that, like many new tools in this conflict, his facial-recognition software is “a technology that shines and only really is appreciated in times of crisis.” But alarmed human-rights groups and privacy advocates warn that unchecked access to his tool, which has been accused of violating privacy laws in Europe, could lead to mass surveillance or other abuses.

That may well be the price of experimentation. “Ukraine is a living laboratory in which some of these AI-enabled systems can reach maturity through live experiments and constant, quick reiteration,” says Jorritt Kaminga, the director of global policy at RAIN, a research firm that specializes in defense AI. Yet much of the new power will reside in the hands of private companies, not governments accountable to their people. “This is the first time ever, in a war, that most of the critical technologies are not coming from federally funded research labs but commercial technologies off the shelf,” says Steve Blank, a tech veteran and co-founder of the Gordian Knot Center for National Security Innovation at Stanford University. “And there’s a marketplace for this stuff. So the genie’s out of the bottle.”—With reporting by Leslie Dickstein and Simmone Shah/New York