Slashdot Mirror

← Back to Stories (view on slashdot.org)

When Bugs Aren't Allowed

Posted by CowboyNeal on from the absolutely-positively-perfect dept.

Coryoth writes "When you're writing software for an air traffic control system, military avionics software, or an authentication system for the NSA, the delivered code can't afford to have bugs. Praxis High Integrity Systems, who were the feature of a recent IEEE article, write exactly that kind of software. In "Correctness by Construction: A Manifesto for High-Integrity Software" developers from Praxis discuss their development method, explaining how they manage such a low defect rate, and how they can still maintain very high developer productivity rates using a more agile development method than the rigid processes usually associated with high-integrity software development."

6 of 489 comments (clear)

  1. nearly unlimited funding by demonbug · · Score: 5, Funny

    probably helps too :P

    1. Re:nearly unlimited funding by GileadGreene · · Score: 5, Interesting

      And yet the reports I've seen on Praxis claim costs and schedules the same or less than the development of software of similar complexity...

  2. No Bugs for NSA? by ChePibe · · Score: 5, Funny

    Uh... it's going to be kind of hard for the NSA to do its job without bugs, isn't it?

    *rimshot*

  3. Bugs are fine... by Paladin144 · · Score: 5, Insightful

    Luckily, bugs are just fine if you happen to run a company that builds voting machines, such as Diebold. And if you think that elections aren't in the same category as air traffic control, I suggest you take a tour of Iraq. Elections are very important for your continued existance upon the earth.

    --
    Electric Monkey Pants
  4. Not unlimited funding by david.emery · · Score: 5, Interesting

    The Master Money server done by Praxis was done Fixed Price, and with a warranty that says Praxis would fix any bug discovered over the net 10 years -for free-.

    How many of you would be willing to place that kind of warranty on YOUR CODE?

    dave (who's tried SPARK and liked it a lot, although proofs are much harder than they should be...)

  5. The right programming language helps hugely by brucehoult · · Score: 5, Interesting

    The site is slashdotted at the moment, so I can't read the article.

    A good example of people writing complex but bug-free software under time pressure is the annual ICFP Programming Contest. This contest runs over three days, the tasks are complex enough that you usually need to write 2000 - 3000 lines of code to tackle them, and the very first thing the judges do is to throw corner-cases at the programs in an effort to find bugs. Any incorrect result or crash and you're out of the contest instantly. After that, the winner is generally the highest-performing of the correct programs.

    Each year, up to 90% of the entries are eliminated in the first round due to bugs, usually including almost all the programs written in C and C++ and Java. Ocassionally, a C++ program will get through and may do well -- even win, as in 2003 when you didn't actually submit your program but ran it yourself (so it never saw data you didn't have a chance to fix it for). But most of the prize getters year after year seem to use one of three not-yet-mainstream languages:

    - Dylan
    - Haskell
    - OCaml

    You can argue about why, and about which of these three is the best, or which of them is more usable by mortals (I pick Dylan), but all of them are very expressive languages with uncluttered code (compared to C++ or Java), completely type-safe, produce fast compiled code, and use garbage collection.