Continuous integration: not landing gear – WINGS

I ran into yet another Continuous Integration project that turned off its CI server after delivery.  Gaaaa! I find it hard to believe, but projects do this.  My only way to understand this is that the managers see CI as just a mechanism to get to release.  And at that point, after all, it's working — isn't it?  It's as if they have gotten their airplane into the sky, and they're pulling up the landing gear so that they can cruise smoothly at 35,000 feet.  The person marginally responsible for keeping CI going decides he's had enough, or the developers don't want to write tests and fix their code as scrupulously as before.  Sometimes management figures it's a good way to save on labor. They are all wrong! Continuous integration - the practice of incessantly rebuilding and retesting your project - is critical to knowing how well it's working.  When you have released your code you are 'flying' on the assumption that all of your successful tests are still successful, and that their dependencies are still satisfied, and its connections, integrations, and services are all just the same.  Are they? And when it comes down to it, verifying all those details is exhaustive.  But that's why you have a large and growing set of unit tests - let the details exhaust your CruiseControl or Hudson or whatever server, not yourself.  You have to keep that going. For this reason I think that your continuous integration activity is your airplane's wings.  If you want to fly and to climb you need those wings.  If you want to see your software succeed and grow you need to be tracking and monitoring it.  Haven't we all worked on software that encountered a sudden lapse in functionality or consistency - and you discover the problem happened weeks ago?  Or months ago?  All the fancy-pants refactoring means nothing when you are caught flat-footed facing a big bug. The software we build now is way too complex to take for granted.  We all take pride in our work, but all sorts of things can happen.  We call it 'bit rot' when a neglected piece of software is found not to work.  So don't neglect it!  When you're done, you've just started.  Keep running and testing it.  Discover quickly when it breaks so you can fix it quickly.  So above all: keep that continuous integration server up and running as long as you have power to run it.