Different goals.<p>Che is focused on workspace portability and interoperability. As a result, there is a hard abstraction between the worksapce and the environments that power it.  the workspace definition includes the definitions of the environments. This makes it possible to move a workspace that is bound to a stack of docker containers containing debugging, runtime, and compilation tools from one node to another node, and then the 2nd node can recreate the entire workspace.<p>Then within this workspace and the machines that are powering it, to embed industry native tools like JDT into it, and then place RESTful wrappers around it so that a browser or other tool may gain access to it.<p>The C9 goal is to build a cloud IDE and provide the best overall experience for developers.  And Che was primarily a focus around workspace movement and interoperability.