It's very easy to use yield-yield with babel. yield-yield and babel will not conflict.
In case of running yield-yield in combination with babel you don't have to run node process with --harmony flag, babel will compile everything into the es5 compatible code.
The syntax will look exactly the same;
var superagent = require('superagent');
var sync = require('yield-yield');
var fs = require('fs');
module.exports = sync(function *() {
//
// Read file from fs
//
var content= yield fs.readFile('/etc/hosts', { encoding: 'utf8'}, yield);
//
// Make the request to the server
//
var response = yield superagent
.get('/api/pet')
.end(yield);
});