Maybe I fill find the time to clean it up and make it public. But did not find VM-types difficult to implement, the type just depends on some run-time value, so at the point in time where the size expression is evaluated, one stores the result in a hidden variable which the type refers to.
Looking forward to the release!
What I found troublesome were not really the caching of array count, but when and where should the side effect be represented in AST, for example this one: https://godbolt.org/z/rcT1d8WWe the puts() call is a side effect for automatic variable but completely ignored for static variable.