I currently have this:
const int = std.fmt.parseInt(i64, str, 10);
try dest.writeAll([]u8{
0x01,
int and 0xFF,
@shrExact(int, 8) and 0xFF,
@shrExact(int, 16) and 0xFF,
@shrExact(int, 24) and 0xFF,
@shrExact(int, 32) and 0xFF,
@shrExact(int, 40) and 0xFF,
@shrExact(int, 48) and 0xFF,
@shrExact(int, 56) and 0xFF,
});
but I am sure that there is a better way to do this (if this even works)