The ability to store your CI build in source control has been a long running request for VSTS and TFS garnering more than 650 votes on user voice. Having your CI defined alongside your application source gives you the ability to evolve your CI as your code evolves and to apply source centric workflows like pull requests and code reviews to your CI. Today we are excited to preview support for defining your VSTS Build pipelines using YAML files checked into your source repository.