The Spy Tech That Became Wall Street’s AI Darling

Barcelona, 2014. Rain had polished Las Ramblas to a wet gleam, and Romuald Fons was hunched in a rented apartment, staring at an Amazon Associates dashboard on his laptop screen — that month’s commission: four hundred and twenty euros. He stubbed out a cigarette into a mug printed with the word “BIGSEO,” a mug he had made himself with transfer paper, back when the company didn’t exist yet, back when it was just the name of a blog without so much as a business license.

The apartment was small. Dishes sat in the kitchen sink, and the fridge held a single jar of olives and half a bottle of cava. His desk was an old door slab laid across two IKEA bookshelves. Three windows were open on the screen: Google Analytics, the Amazon Associates backend, and a half-written review, its title row reading “Rowenta Explorer 60 or 75 — which one is actually worth buying.”

He wrote for seven hours. Not in one uninterrupted flow, but in cycles of drafting and deleting. He would type the same clusters of words into the Spanish search bar again and again — “aspiradora sin bolsa mejor precio,” “Rowenta Explorer opiniones,” “aspirador ciclónico comparativa” — then click open the top twenty results to see what other people’s articles were missing. No real product photos? He went and found real product photos. No noise-level readings in decibels? He dug through German forums, chewing through them with Google Translate. No “how it holds up after six months”? He bought the damn vacuum cleaner and used it for six months. That vacuum cleaner is still in his storage room, its dust bin holding cat hair left over from the move he and his ex-girlfriend made years ago.

The article climbed to third place on Google.es in six weeks. That first month, it sold eleven vacuum cleaners, earning him eighty-seven euros in commission. He did one thing next: he took the same method and applied it to another category — electric toothbrushes. Then kitchen blenders. Then entry-level DSLR cameras. He didn’t write “photography is an art.” He wrote, “Is the Canon EOS 2000D fast enough to photograph your kids in the park at four in the afternoon?”

By the second year, his small network of sites was bringing in four figures in euros every month, steady as clockwork. He called his father and said, “I can make money just by writing.” His father asked, “Did you get a job at a newspaper?” He said no, he wrote product reviews on the internet. There was a silence on the line, and then his father said, “Well, you’d better hope the tax office never finds out.”

Romuald did not get a job at a newspaper. He registered a company called BIGSEO and rented an office in the Gràcia district of Barcelona. The walls disappeared under sheets of keyword matrices; whiteboards carried site-architecture diagrams, arrows pointing from category pages out to dozens of reviews and comparison posts. He hired his first writer, a young woman from Madrid named Marta, a journalism graduate who had previously worked at a content farm, capable of turning out three “buying guides” an hour, every single one of them flagged by Google as low-quality content. Romuald handed her a document. It wasn’t a style guide. It was a set of questions:

“Have you bought this product? If you haven’t used it, don’t write about it. Take it out of the box, plug it in, use it, and then tell me: what made you want to curse? What made you want to recommend it to a friend? Is there a detail the user manual never mentions that you discovered the second time you used it? Write that.”

Marta later told people that it was the first time in her professional life she had ever felt “something I wrote will actually be read.”

Romuald did something a lot of people in the Spanish-speaking SEO world couldn’t understand: he turned his entire method into videos. The YouTube channel was simply his own name. The first video had terrible production quality, shot against the white wall of his office, him in a wrinkled black T-shirt, talking fast in his Catalan-accented Spanish, and the first thing he said was: “If you think SEO is a technical skill, you haven’t even entered the field yet. SEO is understanding what the person on the other side of the keyboard actually wants.”

The comment section split fast. One side said, “Thank you for sharing, finally someone who doesn’t talk in circles.” The other side said, “He’s just trying to ruin the market.” Romuald read that comment (the one about ruining the market) directly into the camera, then said: “This market isn’t ruined. The people who think it’s ruined are just people who can’t see the opportunity anymore. Let me say it again — Spanish-language SEO doesn’t have too much competition. It has too little. So little that if you genuinely understand what the phrase ‘search intent’ means, you’re already in the top five.”

His course later got a name that stuck: “Curso SEO para los FURIOSOS,” the SEO course for the furious. The video covers were his own face, brows furrowed, a finger pointed at the viewer. The course wasn’t cheap, but the conversion rate was extraordinarily high. The reason wasn’t his marketing copy. It was that people had already seen the seventeen screenshots of affiliate-site income he had put out for free, different months, different niches, numbers clear, currency in euros, straight from the Amazon Associates dashboard. See the results first, then decide whether to pay. He never wasted time explaining “why you should learn SEO.” He simply said: “I built a site. It made three hundred thousand euros. You can watch all the free videos and never buy the course. But if you want to get there faster, the course is right here.”

That number (three hundred thousand euros) became his most recognized tag in the Spanish-speaking world. Journalists interviewed him, and headlines read “Spain’s SEO God made 307,000 euros from a single website.” He hated the word “god.” He ranted about it once on video: “Don’t call me a god. Call me someone who knows how to do things. Gods don’t have to wash cat hair off their hands. I do.”

“Washing cat hair” was a real story. Early on, he had run a pet-supply review site. To write a review of a certain type of cat brush, he spent a full week brushing his ex-girlfriend’s cat every single day, collecting data on the amount of fur, taking photos, and eventually discovering that the brush was completely useless on long-haired cats. He wrote that in the review and gave an alternative model. That article became one of the most-cited Spanish-language reviews in the category, not because the writing was beautiful, but because he had actually brushed a cat for a week.

By 2018, BIGSEO was no longer just his own company. Enterprise clients started showing up: local e-commerce brands in Barcelona, companies from Mexico and Argentina. The proposals he gave them were often thin. Thin enough to fit on three slides. Slide one: “This is what’s wrong with your site right now.” Slide two: “This is what your users are actually searching for.” Slide three: “These are the five things we fix in the first round.” One time, a client from Madrid looked at the proposal in a meeting room and got angry. “I’m paying you all this money, and you give me three slides?” Romuald flipped the three printed pages over. The backs were blank. He said: “I can give you thirty pages. But twenty-seven of them would be garbage. Which version do you want?”

The client took the three pages. Three months later, that website’s organic traffic had quadrupled. Romuald turned the story into a video, but he didn’t mention the client’s name. All he filmed was a tree outside that meeting room window. He said: “That conversation made me certain of something: most companies don’t lack information. They lack someone who has the nerve to tell them, ‘You’re wasting your money.’”

His content shifted direction again. He launched a video series called “Pesadilla en la Oficina,” “Nightmare in the Office.” The first episode took him to a family-run lighting business in Valencia, two brothers, one in charge of sales, the other in charge of inventory, who hadn’t had a real conversation about the business in three years. Romuald walked through their warehouse with his phone, filming the shelves of dust-covered stock, the unused router in the corner of the office. Then he sat the two brothers down and said: “You are not running a lighting company. You are using one profitable SKU to feed two hundred unprofitable ones.” He put his pen on the table and added: “Nobody is searching for your products. They’re searching for ‘why is my living room so dark.’ You’ve never written that article.”

That episode exploded on Spanish-language YouTube. Not because it resembled a business documentary, but because it played like a family fight. The older brother said, “I told you this years ago,” and the younger brother said, “You didn’t tell me anything, you just sent a PDF.” Romuald sat between them, his left hand pressed to his temple as if he were physically holding something back. That rawness made viewers feel that this wasn’t “business consulting.” It was “helping a group of people who are terrible at communication finally say the thing out loud.”

In another video later, he said a line that got quoted over and over: “Más trabajo y menos infoproductos.” More work, fewer info-products. That sentence, coming from someone who had built his career on courses, landed with a different weight. He didn’t explain it. He just pointed his camera at the whiteboard in his office, where a new line had been written: “If you can’t help a client see a measurable change in 48 hours, don’t take the project.”

Now. Romuald Fons, founder of the Barcelona SEO firm BIGSEO, creator of the digital marketing school BIG School, a YouTube channel with hundreds of thousands of subscribers. Under his videos, people still argue: some say he’s too arrogant, some say his steps are too specific, not “strategic” enough. But almost none of them deny one thing: he actually did it. The small site that earned €307,418 has been sold. Before selling, he took a final screenshot of the affiliate dashboard; the figure stopped at 307,418. That screenshot still sits in a corner of his website, no filter added.

His most recent public appearance was at a small marketing forum in Madrid. No slides. He walked onstage in jeans. Someone in the audience raised a hand and asked, “Is there still any opportunity in Spanish-language SEO right now?”

He leaned against the edge of a table at the front, took a sip of water, and said: “When I started in 2014, people told me the opportunity was already gone. The fact that you’re asking me that same question now tells me the question will never get old. It’s just that the person answering it needs to actually go build a site, instead of building an argument for why there’s no opportunity left.”

The room went quiet for a second, and then someone started clapping. He waved a hand, quickly adding: “Don’t clap. Go back and write reviews. The kind of review you can only write after you’ve actually used the product. Everything else is noise.”

That evening he went back to Barcelona. The apartment was now a duplex in the city center, no dishes stacked in the kitchen sink, but that door-slab desk was still there. He had never replaced it. The surface held a ring of faint cup stains, soaked in from too much coffee, and too many ashes tapped off too many cigarettes.