in xtask/src/dist.rs [63:69]
fn gzip(src_path: &Path, dest_path: &Path) -> anyhow::Result<()> {
let mut encoder = GzEncoder::new(File::create(dest_path)?, Compression::best());
let mut input = io::BufReader::new(File::open(src_path)?);
io::copy(&mut input, &mut encoder)?;
encoder.finish()?;
Ok(())
}