gulp sourcemap implementation

my gulp sourcemap implementation

var gulp = require('gulp');
var sourcemaps = require('gulp-sourcemaps');

gulp.task('sass', function() {
  return gulp.src(paths.styles.src + 'partials/*.scss')
    .pipe(sourcemaps.init()) // all your piping needs to fit between the sourcemaps.init() and sourcemaps.write()
    .pipe(concat('main.css'))
    .pipe(autoprefixer({
      browsers: ['last 2 versions'],
      cascade: false
    }))
    .pipe(sass({outputStyle: 'compressed'}).on('error', sass.logError))
    .pipe(sourcemaps.write())
    .pipe(gulp.dest(paths.styles.dest));
});