It's not, or only partially. "To try to bridge the gap between high and low level languages, ante adapts a high-level approach by default, maintaining the ability to drop into low-level code when needed." says the website.
Author here, to me the lack of a pervasive tracing GC and values not being boxed by default are important for low level languages. That and maintaining the ability to drop down and use low level constructs like raw pointers for optimization or primitives for new abstractions are essential.
