Managing multiple versions of Ruby on Windows can be a harrowing task since RVM is not present for Windows environment. And suppose you want to install different projects which require different version of Ruby and Rails on Windows.

Can be a challenging task? I don't think so as pik comes to your rescue.

"pik is a tool to manage multiple versions of ruby on Windows. It can be used from the Windows command line (cmd.exe), Windows PowerShell, or Git Bash."

Installation can be tricky at times. So I will take you through a simple tutorial of installing pik and managing your ruby versions.

First and foremost, install which ever ruby versions you require on your system from -

http://rubyinstaller.org/downloads/

It contains the various version of ruby installers.

While installing Ruby do select
Add ruby executables to your PATH

This ensures that you are able to execute ruby files from any directory.

Generally Ruby is installed by default in Drive C if the user did not change the path and the folder name is usually by the name of Rubyversion. (p.s ignoring the dots in between)

For example if you installed Ruby version 2.0.0 then the ruby folder would be by the name of Ruby200.

Then head to

https://github.com/vertiginous/pik/downloads

to download the pik installer. Install pik without changing any options to avoid confusions.

You will also need to install DevKit from

http://rubyinstaller.org/downloads/

"The RubyInstaller Development Kit is a toolkit that makes it easy to build and use native C/C++ extensions such as RDiscount and RedCloth for Ruby on Windows."

Install DevKit and change directory to the installed location from the terminal.

cd <DEVKIT_INSTALLATION_DIRECTORY> 

Then execute the following

ruby dk.rb init

This generates a config.yml file. It contains the installed ruby versions.

Open this config.yml file in a text editor present at

C:\Documents and Settings\user\.pik\config.yml

Note- Here user would be the current user's name. For example on my system the current user is anirudh so the path would be

C:\Documents and Settings\anirudh\.pik\config.yml

The file would contain something like this

--- 
"187: ruby 1.8.7p374 (2013-06-27) [i386-mingw32]": 
  :path: !ruby/object:Pathname 
    path: C:/Ruby187/bin
"193: ruby 1.9.3p448 (2013-06-27) [i386-mingw32]": 
  :path: !ruby/object:Pathname 
    path: C:/Ruby193/bin
--- {}

You can also add a Ruby version if missing. For example I added below one more ruby version

--- 
"187: ruby 1.8.7p374 (2013-06-27) [i386-mingw32]": 
  :path: !ruby/object:Pathname 
    path: C:/Ruby187/bin
"193: ruby 1.9.3p448 (2013-06-27) [i386-mingw32]": 
  :path: !ruby/object:Pathname 
    path: C:/Ruby193/bin
"200: ruby 2.0.0.p353 (2013-06-27) [i386-mingw32]": 
  :path: !ruby/object:Pathname 
    path: C:/Ruby200/bin
--- {}

Here the number 187 , 193 or 200 are the ruby versions minus dots.

To verify the changes done to the config.yml file and whether they are correct or not execute the following

ruby dk.rb review

Finally,

ruby dk.rb install

It enhances your installed Rubies.

According to DevKit website this step installs (or updates) an operatingsystem.rb file into the relevant directory needed to implement a RubyGems preinstall hook and a devkit.rb helper library file into \lib\ruby\site_ruby

Now you are ready to use multiple versions of Ruby in Windows To view the installed ruby versions execute

pik list

To view pik commands execute

pik help commands

On my machine pik list shows the following

187: ruby 1.8.7p374 (2013-06-27) i386-mingw32
193: ruby 1.9.3p448 (2013-06-27) i386-mingw32
200: ruby 2.0.0.p353 (2013-06-27) i386-mingw32

Now to use ruby version 1.9.3 I would use the command

pik 193

Same is the case for ruby 1.8.7

pik 187

Once you start using the required ruby version you can install multiple version of rails as well. Hope this helps in sorting out problems faced on windows system when using pik.