Jetpack Compose: How do you position UI elements within their parent with exact (x,y) coordinates?

According to the documentation on custom layouts: "Each UI element has one parent and potentially many children. Each element is also located within its parent, specified as an (x, y) position, and a size, specified as a width and a height."

Let's say I have a Button inside of a Box. How can I specify the exact X and Y position for the Button inside that Box?

By default Box has TopStart alignment, which is the same as android coordinate space start point. To move from that point you can use offset modifier:

Box {
    Button(
        onClick = { /*TODO*/ },
        modifier = Modifier
            .offset(x = 100.dp, y = 100.dp)
    ) {

    }
}