This principle sounds pretty obvious to software engineers, declaring that a software code should be kept under version control, a single repository, even for multiple deploys. Deploys relate to software instances, running on specific environments. Therefore the codebase of a single application is tracked in a single repository, not several codebases per application or vice versa, containing all specifications for potentially different environments.

This principle leverages developer productivity since all information is found under one repository. It is indifferent to the chosen technology and therefore supported by Java EE applications, as well.

The repository should contain all source files that are required to build and run the enterprise application. Besides Java sources and configuration files, this includes infrastructure as code.