Joan Iglesias wrote: > Hello > > I'm studing Ruby and in a short Ruby in Rails for the web development. > I've observed that each verion of Ruby can introduce modifications in > the sintax and behaviour of Ruby. In the other hand I suppose the > comunity develop libraries in the stable release of the moment. The > question is: > > What about backward compatibilty? If I write a Ruby program using 1.8.5, > in the future I'll be able to run in using the Ruby 2.0? What about the > libraries developed under 1.8 Ruby? > > If I have to develop a professional Ruby program for a company, and one > day I have to update the Ruby's engine, or the ruby's version just > because of a security hole, it would be a bad surprise that nothing > works... > > Someone can clarify all this questions please? I would like to program > in Ruby, but not at any price... > > Thank you very much! Generally, only major version increments introduce backwards incompatibilities. By major version I mean the x in x.y.z. Ruby 1.8 will probably be around even after 2.0 is released, and security and bug updates will surely continue for a while. Cheers, Daniel Schierbeck