Compile & execute Ruby as bytecode. Works in 1.9.3

compiler.rb

#
#
# Compile & execute Ruby as bytecode
#
#
require 'rbconfig'
require 'dl'
require 'fiddle'
require 'strscan'

# This monkey patch allows us to load arbitrary byte code with
# Ruby's VM. Originally from: https://gist.github.com/cstrahan/3552903
class RubyVM
  class InstructionSequence
    handle = DL::Handle::DEFAULT
    address = handle['rb_iseq_load']
    func = Fiddle::Function.new(address, [DL::TYPE_VOIDP] * 3,
                                DL::TYPE_VOIDP)

    define_singleton_method(:load) do |data, parent = nil, opt = nil|
      func.call(DL.dlwrap(data), parent, opt).to_value
    end
  end
end

class Compiler 
  class << self
    # Compile .rb file to .rbc file
    def compile input, output
      seq = RubyVM::InstructionSequence.compile(open(input).read)
      File.write(output, Marshal.dump(seq.to_a))
    end

    # Require a .rbc file
    def require_compiled file
      seq = Marshal.load(File.read(file))
      RubyVM::InstructionSequence.load(seq).eval
    end
  end
end

Compiler.compile('in.rb', 'out.rbc')
Compiler.require_compiled('out.rbc')

Have you tried this is Ruby 2.0?

I keep getting an error:

unknown symbol "rb_iseq_load" (DL::DLError)

I see the function is in the source, but maybe it's been hidden since 1.9?
http://rxr.whitequark.org/mri/source/iseq.c?v=2.0.0-p481#579