Inconsistent character spacing with rust-skia

Question

I'm trying to render some text with rust-skia, but the result has the inconsistent spacing between character.
Here's my code snippet:

...
let font = skia_safe::Font::default();
let paint = skia_safe::Paint::default();

let text = "DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD";
let origin = skia_safe::Point::new(20., 20.);
canvas.draw_str(text, origin, &font, &paint);

What should i do to get the consistent character spacing.