Debug compiled ES6 nodejs app in WebStorm

I want to debug a node app that runs from babel compiled ES6 files. I have my ES6 source in an src folder and the babel ES5 equivalent in a build folder.

Project root
|
| build
| > ES5 Compiled files
|
| src
| > ES6 Source files

My goal: Place breakpoints directly in my ES6 source.

I have generated proper source maps and I made a node debug configuration that runs the ES5 main file with project root set as working directory. I can break when I set breakpoints in ES5 compiled files, and it automatically shows my ES6 source.

However I'd like to place breakpoints directly in the ES6 source.

Is that even possible?