They hacked McDonald’s ice cream machines—and started a cold war


The lure of frozen deliciousness that led to uncovering insane techno craziness.
Enlarge / The lure of frozen deliciousness that led to uncovering insane techno craziness.
NurPhoto | Getty Images

Of all the mysteries and injustices of the McDonald’s ice cream machine, the one that Jeremy O’Sullivan insists you understand first is its secret passcode.

Press the cone icon on the screen of the Taylor C602 digital ice cream machine, he explains, then tap the buttons that show a snowflake and a milkshake to set the digits on the screen to 5, then 2, then 3, then 1. After that precise series of no fewer than 16 button presses, a menu magically unlocks. Only with this cheat code can you access the machine’s vital signs: everything from the viscosity setting for its milk and sugar ingredients to the temperature of the glycol flowing through its heating element to the meanings of its many sphinxlike error messages.

“No one at McDonald’s or Taylor will explain why there’s a secret, undisclosed menu,” O’Sullivan wrote in one of the first, cryptic text messages I received from him earlier this year.

As O’Sullivan says, this menu isn’t documented in any owner’s manual for the Taylor digital ice cream machines that are standard equipment in more than 13,000 McDonald’s restaurants across the US and tens of thousands more worldwide. And this opaque user-unfriendliness is far from the only problem with the machines, which have gained a reputation for being absurdly fickle and fragile. Thanks to a multitude of questionable engineering decisions, they’re so often out of order in McDonald’s restaurants around the world that they’ve become a full-blown social media meme. (Take a moment now to search Twitter for “broken McDonald’s ice cream machine” and witness thousands of voices crying out in despair.)

But after years of studying this complex machine and its many ways of failing, O’Sullivan remains most outraged at this notion: That the food-equipment giant Taylor sells the McFlurry-squirting devices to McDonald’s restaurant owners for about $18,000 each, and yet it keeps the machines’ inner workings secret from them. What’s more, Taylor maintains a network of approved distributors that charge franchisees thousands of dollars a year for pricey maintenance contracts, with technicians on call to come and tap that secret passcode into the devices sitting on their counters.

The secret menu reveals a business model that goes beyond a right-to-repair issue, O’Sullivan argues. It represents, as he describes it, nothing short of a milkshake shakedown: Sell franchisees a complicated and fragile machine. Prevent them from figuring out why it constantly breaks. Take a cut of the distributors’ profit from the repairs. “It’s a huge money maker to have a customer that’s purposefully, intentionally blind and unable to make very fundamental changes to their own equipment,” O’Sullivan says. And McDonald’s presides over all of it, he says, insisting on loyalty to its longtime supplier. (Resist the McDonald’s monarchy on decisions like equipment, and the corporation can end a restaurant’s lease on the literal ground beneath it, which McDonald’s owns under its franchise agreement.)

So two years ago, after their own strange and painful travails with Taylor’s devices, 34-year-old O’Sullivan and his partner, 33-year-old Melissa Nelson, began selling a gadget about the size of a small paperback book, which they call Kytch. Install it inside your Taylor ice cream machine and connect it to your Wi-Fi, and it essentially hacks your hostile dairy extrusion appliance and offers access to its forbidden secrets. Kytch acts as a surveillance bug inside the machine, intercepting and eavesdropping on communications between its components and sending them to a far friendlier user interface than the one Taylor intended. The device not only displays all of the machine’s hidden internal data but logs it over time and even suggests troubleshooting solutions, all via the web or an app.

The result, once McDonald’s and Taylor became aware of Kytch’s early success, has been a two-year-long cold war—one that is only now turning hot. At one point, Kytch’s creators believe Taylor hired private detectives to obtain their devices. Taylor recently unveiled its own competing Internet-connected monitoring product. And McDonald’s has gone so far as to send emails to McDonald’s franchisees, warning them that Kytch devices breach a Taylor machine’s “confidential information” and can even cause “serious human injury.”

After watching the efforts of McDonald’s and Taylor decimate their business over the five months since those emails, O’Sullivan and his cofounder are now on the counterattack: The Kytch couple tells WIRED they’re planning to file a lawsuit against some McDonald’s franchisees who they believe are colluding with Taylor by handing over their Kytch devices to the ice cream machine giant and allowing them to be reverse-engineered—a violation of the franchisees’ agreement with Kytch. (Taylor denies obtaining Kytch devices but doesn’t deny trying to gain possession of one or that a Taylor distributor did ultimately access it.) The lawsuit will likely be only the first salvo from Kytch in a mounting, messy legal battle against both Taylor and McDonald’s.

But in his initial messages to me, O’Sullivan mentioned none of the details of this escalating conflict. Instead, with Hamburglar-like slyness, he dared me to pull on a loose thread that he suggested could unravel a vast conspiracy. “I think you could blow this story open by just asking a simple, very reasonable question,” O’Sullivan’s first text messages concluded: “What’s the real purpose of this hidden menu?”

The Ferrari of soft serve?

The standard Taylor digital ice cream machine in a McDonald’s kitchen is “like an Italian sports car,” as one pseudonymous franchisee who uses the Twitter nom de guerre McD Truth described it to me.

When the hundreds of highly engineered components in Taylor’s C602 are working in concert, the machine’s performance is a smooth display of efficiency and power: Like other ice cream machines, it takes in liquid ingredients through a hopper and then freezes them in a spinning barrel, pulling tiny sheets of the frozen mixture off the surface of the barrel’s cold metal with scraper blades, mixing it repeatedly to create the smallest possible ice crystals, and then pushing it through a nozzle into an awaiting cup or cone.

But the ice cream machine Taylor has invented for McDonald’s is special: It has two hoppers and two barrels, each working independently with precise settings, to produce both milkshakes and soft serve simultaneously. It uses a pump, rather than gravity like many other machines, to accelerate the flow of McFlurries and fudge sundaes: McD Truth describes selling 10 ice cream cones a minute during peak sales periods, a feat that’s impossible with other machines.

And while other ice cream machines have to be disassembled and cleaned daily—and any leftover contents discarded—McDonald’s Taylor machines use a daily “heat treatment” process designed to jack up its contents’ temperature to 151 degrees Fahrenheit, pasteurize it for a minimum of 30 minutes, and then refreeze it again in a once-a-night cycle, a modern marvel of hygiene and cost savings.

But in keeping with McD Truth’s Italian sports car analogy, these machines are also temperamental, fragile, and ridiculously overengineered. “They work great as long as everything is 100 percent perfect,” McD Truth writes. “If something isn’t 100 percent, it will cause the machine to fail.” (McDonald’s agreement with franchisees also allows them to use an actual Italian machine, sold by Bologna-based Carpigiani, that McD Truth describes as much better designed. But given that its replacement parts can take a week to arrive from Italy, far fewer restaurants buy it.)

Every two weeks, all of Taylor’s precisely engineered components have to be disassembled and sanitized. Some pieces have to be carefully lubricated. The machine’s parts include no fewer than two dozen rubber and plastic O-rings of different sizes. Leave a single one out, and the pump can fail or liquid ingredients can leak out of the machine. One McDonald’s franchisee’s tech manager told me he’s reassembled Taylor’s ice cream machines more than a hundred times, and had them work on the first try at most 10 of those times. “They’re very, very, very finicky,” he says.

The machine’s automated nightly pasteurization process, rather than make life easier for restaurant managers, has become their biggest albatross: Leave the machine with a bit too much or too little ingredient mixture in its hoppers, accidentally turn it off or unplug it at the wrong moment, or fall victim to myriad other trivial errors or acts of God, and the four-hour pasteurization process fails and offers a generic, inscrutable error message—meaning that the machine won’t work until the entire four hours of heating and freezing repeats, often in the middle of peak ice cream sales hours.

A Kytch device
Enlarge / A Kytch device

The result can be hundreds of dollars in sales immediately lost. (Especially, O’Sullivan explains, during “shamrock season,” when McDonald’s offers a St. Patrick’s Day–themed mint-green milkshake that boosts shake sales as much as tenfold. “Shamrock season is a big fucking deal,” O’Sullivan emphasizes.)

Taylor sells a machine with these technical demands to businesses where they’ll ultimately be run by a bored teenager whose fast-food career is measured in weeks. So perhaps it’s no surprise that many McDonald’s restaurants’ ice cream machines seem to be as often broken as not. The website McBroken.com, which uses a bot to automatically attempt to place an online order for ice cream at every McDonald’s in America every 20 to 30 minutes and measures the results, reveals that at any given time over the past two months, somewhere between 5 and 16 percent of all US McDonald’s are unable to sell ice cream. On a typical bad day as I reported this piece, that included one out of five McDonald’s in Los Angeles, Washington, DC, and Philadelphia, one out of four in San Francisco, and three out of 10 in New York City.

Plenty of companies have fought against their own customers’ right-to-repair movements, from John Deere’s efforts to prevent farmers from accessing their own tractors’ software to Apple’s efforts to limit who can fix an iPhone. But few of those companies’ products need to be repaired quite so often as McDonald’s ice cream machines. When WIRED reached out to McDonald’s for this story, the company didn’t even attempt to defend the machines’ shambolic performance. “We understand it’s frustrating for customers when they come to McDonald’s for a frozen treat and our shake machines are down—and we’re committed to doing better,” a spokesperson wrote.

On social media, meanwhile, the McDonald’s ice cream meme has come to represent everything disappointing about modern technology, capitalism, and the human condition. When three women in Florida attacked a McDonald’s employee after learning the ice cream machine was broken in 2017, a significant fraction of the Twitter reactions sided with the attackers. McDonald’s itself tweeted from its official account last August that “we have a joke about our soft serve machine but we’re worried it won’t work,” a self-own that received nearly 29,000 likes.

On a recent evening in March, I attempted to tally the number of people who tweeted some version of the joke that they were going to spend their $1,400 Covid stimulus payment to fix their local McDonald’s ice cream machine. I lost count at 200.