JavaScript ECMA 6 project

I would like to set up a JavaScript ECMA 6 project. But I'm insecure about the general approach.

I've set up a project with Jasmine 2.5.3 and Karma 1.5 (and Chutzpah) but it seems that they don't support ECMA 6. (Arrow functions are not working for example)

Did I miss something - do Jasmine and Karma support EMCA 6? Or do I first have to compile ECMA 6 code (with babel) into ECMA 5 code?

Regards