I believe that what we're seeing is declarative paradigm used as subsystems / domain specific languages that do a particular core task accurately and efficiently, but surrounded with a general purpose "scripting environment" in which you do the messy interfaces with the surrounding world and users.
Besides the obvious SQL example, the current ML systems such as Tensorflow are a great illustration; you declare a particular computation graph and then the system "just executes it" over multiple GPUs.
Besides the obvious SQL example, the current ML systems such as Tensorflow are a great illustration; you declare a particular computation graph and then the system "just executes it" over multiple GPUs.