feat: Will "Custom Linear Operator" also work for "black box" code?

[mreineck]

I'm working on a collection of optimized linear operators, including FFTs, non-uniform FFTs, spherical harmonic transforms etc. (see https://github.com/mreineck/ducc if you are interested in more details). These are implemented in C++, but callable through a simple Python interface. For every operator I'm providing forward application as well as the adjoint.
It would be great to make Jax aware of these operations, but at least at the moment there doesn't seem to be an easy way to do this. Will your "Custom Linear Operator" enhancement be able to support this kind of code, or will it be limited to Python code that is fully inspectable by Jax?