My Ruby compiler is, I'm sad to say, languishing. I got it to a stage where it does compile itself successfully (to 32 bit x86 assembly - 32 bit was still a reasonable choice when I started...), but it has plenty of bugs (and only compiles itself due to workarounds for those in the compiler source to avoid triggering them) and doesn't support most newer Ruby syntax, nor Regexp's or Float's (other massively limitations too). I keep telling myself I should at least fix the bugs at some point and strip out the workarounds, but so many other projects at the moment.