Cloud platform to be unveiled backing frameworks like Rails and Merb Heroku will debut on Friday its cloud service for Ruby applications, competing with Google and offering provisionless Web hosting.The Heroku service offers an agile platform for development, testing and production deployment of Web applications. Deployed on the Amazon cloud platform, Heroku is a multi-tenant platform for applications written in Ruby and running on Rack-compatible frameworks including Rails, Merb, and Sinatra.[ Related: Ruby on Rails on track for major upgrades. ] Featured in Heroku are automated management and scaling, the company said. “It provides single-step deployment of Web applications in a way that just works, without configuration,” said James Lindenbaum, CEO and co-founder of Heroku.Heroku sees itself as a competitor to the Google App Engine platform for hosting of applicatiopns but believes it offers a more “open” platform featuring an Ingres database and other open source components, Lindenbaum said.Heroku has been in a beta stage for a year and has attracted 25,000 applications, Lindenbaum said. Three types of applications are featured on Heroku: Enterprise applications, such as business process systems; Web 2.0 applications, such as consumer systems; and individual applications built by persons such as hobbyists. Applications deployed to Heroku are compiled into a read-only instance called a “slug.” An activated application on the platform is called a dyno, serving as a process running on the server in a grid.Users pay for resources they consume, with enterprise deployments costing about $5,000 to $10,000 per month. Cloud Computing