This project hosted a portable Ruby 2.1.3 runtime for Windows with a host of associated utilities, but this project is now retired. The last state of the repository can still be found in the retired tag but we strongly advise against using these tools as Ruby 2.1 is no longer maintained and the binaries within may have unpatched security vulnerabilties.
As an alternative, you can assemble a Windows ruby environment from these sites pretty easily:
This project served as an adjunct to cucumber-watir which has instructions in its README about putting together a Selenium test suite using Cucumber, Watir, chrome-webdriver and InternetExplorerDriver.