The author outlines a fair bit of the design thinking in this post [0].
What Datalog and co give you is the ability to do interesting program transformations. Mostly that's not because they are "declarative", if that means anything, but because they avoid all the little bits of non-determinism that imperative languages include. If you avoid those you're pretty much set. Coming from another angle, JAX [1] shows how you can do program transformations in Python with a relatively small set of semantic restrictions.
What Datalog and co give you is the ability to do interesting program transformations. Mostly that's not because they are "declarative", if that means anything, but because they avoid all the little bits of non-determinism that imperative languages include. If you avoid those you're pretty much set. Coming from another angle, JAX [1] shows how you can do program transformations in Python with a relatively small set of semantic restrictions.
[0]: https://www.scattered-thoughts.net/writing/unexplanations-sq... [1]: https://github.com/jax-ml/jax