The gherkin language that cucumber uses for its specifications, written well, are brilliant at distilling what the customer wants, what the developer is going to build and how the QA is going to assert that acceptance is measured. But it has to be written collaboratively by all of those together and by the end of it you get a shared understanding. This is the most important part.

The glue code behind it is a different fish, and needs someone with software engineering trainging to build it and love it.