commander 0.1.5

The complete solution for Rust command-line interfaces
Documentation
// build.rs
extern crate chrono;
use chrono::prelude::*;

use std::env;
use std::fs::File;
use std::io::Write;
use std::path::Path;

fn main() {
    let out_dir = env::var("OUT_DIR").unwrap();
    let dest_path = Path::new(&out_dir).join("build_timer.rs");
    let mut f = File::create(&dest_path).unwrap();
    let utc: DateTime<Utc> = Utc::now();       // e.g. `2014-11-28T12:45:59.324310806Z`
    let timer = format!("{}",utc).to_string();
    f.write_all(b"pub fn get_build_time() -> &'static str {\n\t\"").unwrap();
    f.write_all(timer.as_bytes()).unwrap();
    f.write_all(b"\"\n}").unwrap();
}