It's a non-issue. If you can build it, someone else can (and will). If your business is dependent upon the idea itself you are probably doomed or at least in for a hell of a fight. Anyone with funding could always come along with 10x the cash and resources to throw at the problem.

I recommend designing and building a business around some kind of competitive advantage, like data. In that case, even if your competitors have all of your code they still can't compete with you.