I would like a language where your call stack can't be bigger than two/three. You can call functions inside your function Main, but these function can't call a

I would like a language where your call stack can't be bigger than two/three. You can call functions inside your function Main, but these function can't call any functions anymore (exception being flat helper functions defined inside your function). I think it would save a huge chunk of time by just having all programs really nice and flat. You'd naturally gravitate towards mechanisms that make programs flat.