Oh, and forward compatibility. Now optimization is definitely more Greg’s kind of thing than mine, and Marcus doesn’t have much spare time these days, so I took it on myself to focus on that other thing. I went to look at PHP 6. The good news is that from now, all phars created using PHP 5.2.1 and up should run under PHP 6 and vice versa. The structure’s unchanged. Sing hallelujah. The bad news is that a phar with a default stub won’t run under versions of PHP prior to PHP 5.2.1, whereas we had PHP 5.1 support this time last week. Blame: b and the binary cast. The default stub calls unpack(), you see, and PHP 6 needs to be told that the second argument to unpack() is a binary string and not a Unicode string. The only ways we have of telling PHP 6 this will throw a parse error in PHP 5.2.0 and under. There’s no way to have both backward compatibility and forward compatibility: we have to choose....