I have both MRI and JRuby installed on my systems. For quickie scripts I use 'ruby' and for anything with a noticeable runtime (Or multi-core processing!) I use

I have both MRI and JRuby installed on my systems. For quickie scripts I use 'ruby' and for anything with a noticeable runtime (Or multi-core processing!) I use 'jruby'. I'm sure the JRuby fellows will continue working on startup time, but for me at least, it's not an issue. I think having a Ruby toolbox instead of a single big hammer is a win for everybody.