This is my demo using angularjs, for creating a service file, and adding service to a controller.
I have two problems with my demo:
I had the same problem, but I forgot to include the file into grunt/gulp minimization process.
grunt.initConfig({ uglify: { my_target: { files: { 'dest/output.min.js': ['src/input1.js', 'src/missing_controller.js'] } } } });
Hope that helps.