Looking in the source tree, it doesn't look like it has it's own entry point. Zig is heading in the direction of a very verticall integrated compilation stack (I believe this is where most of the speed up comes from), so I'm not really sure of the utility with using it outside of the Zig world.
https://github.com/jacobly0/zig/tree/4508c2543508e04253471e1... https://github.com/jacobly0/zig/blob/4508c2543508e04253471e1...