>> I'd still want a build server to ensure I hadn't managed to pollute my dev environment with and undeclared dependency before I pushed my code to production.

>> I'd still want a build server to ensure I hadn't managed to pollute my dev environment with and undeclared dependency before I pushed my code to production. >In my case, the production server is the build server. You can't have dev dependencies there, because you don't develop there. The problem is not that dev dependencies exist, the problem is that they might be undeclared or unrecorded. I have imagemagic on my dev machine, but if it isn't installed as part of the server setup script, then it won't be on the production server. The tests might run fine on a dev server that happens to have imagemagic on it, but fail in production. >Integration tests run on the dev If you run your integration tests in your dev environment, you might not catch some on the fly configuration changes or utility installations - undeclared dependencies.