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To engage in this kind of assemblage of functionality is bracingly logical and orderly; you feel like you are making a perfect little machine, a clean, comprehensible automaton that you have set in motion. But soon, as you adapt your procedural engine for the exceptions, for all the variations that exist in the real world, you find yourself snarled in squirming thickets of if-then-else constructs, each of which contains yet other if-elseif and switch-case monsters, and you find that you have to break out of your beautiful Report-Main-Body loop and backtrack to other reports to retrieve history, and then, inevitably your procedures become more complex and start doing two things instead of one, RetrievePatientInfo() is now doing the retrieving but is also checking for valid addresses, you know that functionality should be somewhere else but you don’t have the time to bother, the users ask for a new feature and you patch it in, and of course you mean to come back later and clean everything up, but then, before you know it, you are trapped inside an unwholesome, uncontrollable atrocity, a Big Ball of Mud: “[a] haphazardly structured, sprawling, sloppy, duct-tape and bailing wire, spaghetti code jungle.”6
Often, it is not the lack of programming skill that leads to the emergence of a Big Ball of Mud, but something akin to the time-honored Indian practice of jugaad. Jugaad is Hindi for a creative workaround, a working improvisation that is built in the absence of resources and under pressure of time (from the Sanskrit yukti, trick, combination, concatenation). There can be something heroic about jugaad, as in the strange-looking trucks one sees bumping down country roads in rural India, which on closer examination turn out to be carts with diesel irrigation pumps strapped on; or the amphibious bicycles buoyed by improvised air floats and powered by blades taken from ceiling fans. Jugaad makes do, it gets work done, it maneuvres around uncooperative bureaucracies, it hacks. In recent years, jugaad has been recognized as down-to-earth creativity, as a prized national resource, and has acquired the dignifying sobriquet of “frugal engineering.”
In software, repeated applications of excessively frugal engineering by a series of programmers leads to a scheme that has no discernible structure, within which components use each other’s functionality promiscuously, so that the logic of the program becomes hard or impossible to follow. In a Big Ball of Mud — and yes, it is a technical term of art — effects flow across boundaries, so that introducing a small change to one piece of code results in unpredictable behavior in distant parts of the system. Software needs maintenance: bugs need to be fixed, new features are demanded by users. If you are the programmer asked to go into the depths of a Big Ball of Mud, the prospect is terrifying. I mean that quite literally; as you poke and prod into the i
For instance: the US Pentagon’s Defense Finance and Accounting Service (DFAS) is known to make “widespread” errors in paying soldiers’ salaries, and is slow to correct these mistakes when challenged. The software that the Pentagon uses for payroll and accounting comprises about seven million lines of COBOL code, mostly written in the sixties. The system hasn’t been updated in more than a dozen years, and significant portions of the code have been “corrupted”—long-ru
When a situation like this becomes desperate enough, the powers-that-be may employ skilled “code archaeologists” to spelunk into the depths. Or pony up for a complete rewrite. Mostly, managers prefer to plug up the holes and leave the Big Balls of Mud to roll on. COBOL, a language first introduced in 1959 by Grace Hopper (“Grandma COBOL”), still processes 90 percent of the planet’s financial transactions, and 75 percent of all business data.8 You can make a comfortable living maintaining code in languages like COBOL, the computing equivalents of Mesopotamian cuneiform dialects. These ancient applications — too expensive to replace, sometimes too tangled to fix or improve — run on, serving up the data that appears on the chromed-up surface of your browser, which gives you the illusion that your bank and your local utility companies live on the technological cutting edge. But as always, the past lives on under the shiny surface of the present, and often, it is too densely tangled to comprehend.
The International Obfuscated C Code Contest a
brainfuck is a “Turing tarpit,” which is to say it is a very small language in which you can write any program that you could write in C or Java; but attempting to do so would, well, fuck your brain, and therefore the delectable frisson of terror the code above induces in discerning code cognoscenti. brainfuck is venerable and famous, but my favorite esoteric language is Malbolge, which was designed solely to be the most outrageously difficult language to program in. It is named, appropriately, after the eighth circle of hell in Dante’s Inferno, Malebolge (“Evil ditches,” reserved for frauds). In the language Malbolge, the result of any instruction depends on where it is located in memory, which effectively means that what specific code does changes with every run. Code and data are very hard to reuse, and the constructs to control program flow are almost nonexistent.11 Malbolge inverts the sacred commandments of literate programming, and is so impenetrable that it took two years after the language was first released for the first working program to appear, and that program was not written by a human, but generated by a computerized search program that examined the space of all possible Malbolge programs and wi