var gulp = require('gulp'); var gutil = require('gulp-util'); var babel = require('gulp-babel'); var cache = require('gulp-cached'); var remember = require('gulp-remember'); var plumber = require('gulp-plumber'); var source = ["src/**/*.js"] gulp.task('babel', function() { return gulp.src(source) .pipe(plumber()) .pipe(cache("babel")) .pipe(babel({presets: ["es2015"]}).on('error', gutil.log)).on('data', gutil.log) .pipe(remember("babel")) .pipe(gulp.dest("lib/")); }); gulp.task('watch', function () { gulp.watch(source, ['babel']); }); gulp.task('default', ['babel', 'watch']);