Constraint solvers and geometry kernels are big, very expensive, beasts of software.  They have grown over the decades, bit by bit, research yielding new approaches, as well as empirical, &quot;Hey, I couldn&#x27;t make this.&quot; use cases contributing to a very smart body of code with millions of man hours in it.<p>Setting this tech aside, I would still classify CAD as an unsolved problem space.  Even advanced kernels can and do fail, or generate erroneous geometry on what one would think is a common, or simple use case.<p>That said, we are getting really good at basic geometry now.  Those basic cases are much fewer and far between with most users just seeing robust operation now.  It&#x27;s taken many years for this to happen, marking time at the dawn of affordable solid modeling CAD in the mid 90&#x27;s.<p>Now, it&#x27;s about getting computers to do what people can do, and that&#x27;s infer intent as we do with our minds eye and analytic skill.  It&#x27;s also continuing to be about feature create, and that&#x27;s all about how to boil down the UX of shape and intent description to the system.  Also quite challenging.<p>This kind of thing, as a branch in the &quot;what&#x27;s possible with CAD?&quot; tree is pretty damn exciting!  There are going to be a whole class of great use cases for this in the near future.<p>Bear in mind, old feature create means and methods almost never die.  They get sidelined, used less, whatever, but they continue to exist because there continue to be use cases they are excellent for.<p>A lot of people think, &quot;replace&quot; when the real questions should be, &quot;Add to, and what new things can we do?&quot;