Ledinot and Berry worked for nearly 10 years to get Esterel to the point where it could be used in production. Part of the draw for customers, especially in aviation, is that while it is possible to build highly reliable software by hand, it can be a Herculean effort. Ravi Shivappa, the VP of group software engineering at Meggitt PLC, an ANSYS customer which builds components for airplanes, like pneumatic fire detectors for engines, explains that traditional projects begin with a massive requirements document in English, which specifies everything the software should do.
And when the customer changes the requirements, the code has to be changed, too, and tested extensively to make sure that nothing else was broken in the process. The cost is compounded by exacting regulatory standards. The FAA is fanatical about software safety. The agency mandates that every requirement for a piece of safety-critical software be traceable to the lines of code that implement it, and vice versa. So every time a line of code changes, it must be retraced to the corresponding requirement in the design document, and you must be able to demonstrate that the code actually satisfies the requirement.
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Much of the benefit of the model-based approach comes from being able to add requirements on the fly while still ensuring that existing ones are met; with every change, the computer can verify that your program still works. Still, most software, even in the safety-obsessed world of aviation, is made the old-fashioned way, with engineers writing their requirements in prose and programmers coding them up in a programming language like C.
As Bret Victor made clear in his essay, model-based design is relatively unusual. Most programmers feel the same way. They like code. At least they understand it. It is a pattern that has played itself out before. Whenever programming has taken a step away from the writing of literal ones and zeros, the loudest objections have come from programmers. Emmanuel Ledinot, of Dassault Aviation, pointed out that when assembly language was itself phased out in favor of the programming languages still popular today, like C, it was the assembly programmers who were skeptical this time.
I n , Chris Newcombe had been working at Amazon for almost seven years, and had risen to be a principal engineer. He is one of those engineers whose work quietly keeps the internet running. But all he could think about was that buried deep in the designs of those systems were disasters waiting to happen. A single subtle bug could be catastrophic. But he knew how hard bugs were to find, especially as an algorithm grew more complex. In practice, it allowed you to create a realistic model of your problem and test it not just thoroughly, but exhaustively.
These specifications can then be completely verified by a computer. If not, it will show you exactly how they could be violated. The language was invented by Leslie Lamport, a Turing Award—winning computer scientist. With a big white beard and scruffy white hair, and kind eyes behind large glasses, Lamport looks like he might be one of the friendlier professors at the American Hogwarts.
And there is a patient joy, a meditative kind of satisfaction, to be had from puzzling out the micro-mechanics of code. But code, Lamport argues, was never meant to be a medium for thought. It is now used widely at the company. Engineers at the European Space Agency used it to rewrite, with 10 times less code, the operating system of a probe that was the first to ever land softly on a comet.
Intel uses it regularly to verify its chips. Even to a seasoned engineer like Newcombe, the language read at first as bizarre and esoteric—a zoo of symbols. For Lamport, this is a failure of education. Though programming was born in mathematics, it has since largely been divorced from it. Because they never learned it. Complexity is the biggest challenge for programmers.
Programmers, as a species, are relentlessly pragmatic. Most programmers who took computer science in college have briefly encountered formal methods. For him, using these tools is now a matter of responsibility. There were at least five Fiat Chrysler models affected, including the Jeep Cherokee. One day they could have told them all to, say, suddenly veer left or cut the engines at high speed.
Car companies have long assembled their final product from parts made by hundreds of different suppliers. But where those parts were once purely mechanical, they now, as often as not, come with millions of lines of code. And it has made possible a new kind of failure.
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Emmanuel Ledinot, of Dassault Aviation, speculates that there might be economic reasons for the difference, too. One suspects the incentives are changing. Code will be put in charge of hundreds of millions of lives on the road and it has to work. That is no small task. When your software is broken, you look at your software, you see nothing.
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Milton Abel II reflects on the event that led to his decision to leave the upper echelon of the restaurant world. Her Instagram account reads like Brideshead Revisited meets Twilight meets Vanity Fair magazine circa , when greed was good and having money was a golden superpower. Let us begin with the 45 servings of eggplant salad made in the tiny kitchen of a studio apartment in Greenwich Village, transported to a Brooklyn loft, and served as a homemade lunch to ticketed guests.
It was so tasty that many people asked for—and were generously given, at no extra cost—second helpings. If you are running a short con that involves driving eggplant salad to another borough, you might as well find honest work, because you lack the grifter mentality. The majority of her followers are young white women, a demographic not underrepresented in the world of media, and so—improbably enough—this micro-event was covered just about everywhere, including in The New York Times, The Washington Post , NBC, you name it. The whistle-blower scandal that has prompted the fourth presidential impeachment process in American history has put a spectacle from earlier this decade back on display: the jaw-smacking feast of scavengers who circled around Ukraine as Viktor Yanukovych, a Moscow-linked kleptocrat, was driven from power.
The renewed focus on Ukraine raises jangling questions: How did dealing in influence to burnish the fortunes of repugnant world leaders for large payoffs become a business model? It will allways afford me pleasure I assure you, to hear from you.
The Coming Software Apocalypse
One of the worst maritime disasters in European history took place a decade ago. It remains very much in the public eye. On a stormy night on the Baltic Sea, more than people lost their lives when a luxurious ferry sank below the waves. From a mass of material, including official and unofficial reports and survivor testimony, our correspondent has distilled an account of the Estonia's last moments—part of his continuing coverage for the magazine of anarchy on the high seas. After midnight, in the first hours of September 28, , the ferry Estonia foundered in the waves of a Baltic storm.
The ship was the pride of the newly independent Estonian nation, recently arisen from the Soviet ruins. It was a massive steel vessel, feet long and nine decks high, with accommodations for up to 2, people. It had labyrinths of cabins, a swimming pool and sauna, a duty-free shop, a cinema, a casino, a video arcade, a conference center, three restaurants, and three bars.
It also had a car deck that stretched from bow to stern through the hull's insides. In port the car deck was accessed through a special openable bow that could be raised to allow vehicles to drive in and out. At sea that bow was supposed to remain closed and locked. In this case, however, it did not—and indeed it caused the ship to capsize and sink when it came open in the storm and then fell entirely off.
All they had to do was play by the rules. He stood before its Memorial Wall, which then had stars commemorating those who lost their lives in the line of duty. Then Trump joked about asking for a show of hands to see who in the room had voted for him. He went on a diatribe about the news media. He repeated lies, at length, about the size of the crowd at his inauguration. The blowback was swift. Former CIA directors were angered and concerned. One U. Farhad Yusef-Zadeh was observing the center of the Milky Way galaxy in radio waves, looking for the presence of faint stars, when he saw it: a spindly structure giving off its own radio emissions.
The filament-like feature was probably a glitch in the telescope, or something clouding the field of view, he decided. But the mystery filament kept showing up, and soon Yusef-Zadeh found others.
What the astronomer had mistaken for an imperfection turned out to be an entire population of cosmic structures at the heart of the galaxy. The menagerie of filaments is clustered around the supermassive black hole at the center of our galaxy. When Donald Trump stepped to the dais at the United Nations General Assembly yesterday, he had a speech full of sharp lines: swipes at socialism, assertions of nationalism versus globalism, harsh words for Iran.
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