I recommend these handy little things called "tests". When all else fails, do the right thing.
The devil is out to steer you onto the wrong path.
I'm convinced that they are not suited for large-scale software development...I guess if I listened to the devil, he'd have me recall all those large-scale applications I've written over the last 25 years that have designed electronics, moved things through factories, dispatched equipment in hurricanes, and so on because they're not written in a suitable language.
Beware the devil. Over on the devil's own blog...
I think there [a solution]: dynamic languages that allow you to type your variables if you feel like it, and the only language that I can think of that does that at the moment is Groovy.Well, let's see. Common Lisp had that about 22 years ago. Maybe there's something to learn from a couple decades of real experience? Conclusion? Feh.
This is the devil that used to want you to program in C, not Smalltalk. Then C++, not Smalltalk. Then Java, not Smalltalk. Now he's willing to give you Smalltalk if you type your objects once in a while.
Don't listen to the devil. Write tests in simple, dynamic languages. Do good work. Keep the devil at bay.