working sourcemaps

gulpfile.js

var gulp = require('gulp'),
    sass = require('gulp-sass');
var config = {
    sass: {
        includePaths: [],
        sourceComments: 'map'
    }
};
gulp.task('compile-sass', function() {
    gulp.src('public/assets/css/*.scss')
        .pipe(sass(config.sass))
        .pipe(gulp.dest('public/css'));
});


gulp.task('watch', [ 'compile-sass'], function() {
    gulp.watch(['public/assets/stylesheets/**/*.scss'], ['compile-sass']);
});

gulp.task('default', ['watch']);