How to work on the console when you have a ruby project you want to try? If you are tweaking the code I believe that gem install … is not the solution.
So, I found a solution here: http://stackoverflow.com/questions/5424905/automatically-load-projects-environment-to-irb
What you can do is
irb -Iname_of_libfolder -rname_of_rb_file
for example for me that was irb -Ilib -rwp_rpc