Can unit testing be successfully added into an existing production project? If so, how and is it worth it?

Question

I\'m strongly considering adding unit testing to an existing project that is in production. It was started 18 months ago before I could really see any benefit of TDD

Answer 1

It depends...
It's great to have unit tests but you need to consider who your users are and what they are willing to tolerate in order to get a more bug-free product. Inevitably by refactoring your code which has no unit tests at present, you will introduce bugs and many users will find it hard to understand that you are making the product temporarily more defective to make it less defective in the long run. Ultimately it's the users who will have the final say...