gulp browserify reactify task is quite slow

Question

I am using Gulp as my task runner and browserify to bundle my CommonJs modules.

I have noticed that running my browserify task is quite slow, it takes around 2 - 3 seco

Answer 1

Many thanks to @PHaroZ for that answer. I had to modify a little bit that code for my needs though. I am working with ReactJS on Symfony2 framework and all my builds were taking 7s-21s!!! Crazy.. So that's what I have now:

var path = {
    OUT : 'app.js',
    DEST_BUILD : './src/MyBundle/Resources/js/dist',
    ENTRY_POINT : './src/MyBundle/Resources/js/src/app.js'
};

gulp.task('watch', [], function() {
    var bundler = browserify({
        entries : [ path.ENTRY_POINT ],
        extensions : [ ".js", ".jsx" ],
//        transform : [ 'reactify' ],
        debug : true,
        fullPaths : true,
        cache : {}, // <---- here is important things for optimization
        packageCache : {} // <----  and here
    }).transform("babelify", {presets: ["es2015", "react"]});
    bundler.plugin(watchify, {
//      delay: 100,
//      ignoreWatch: ['**/node_modules/**'],
//      poll: false
    });

    var rebundle = function() {
        var startDate = new Date();
        console.log('Update start at ' + startDate.toLocaleString());
        return bundler.bundle(function(err, buf){
                if (err){
                    console.log(err.toString());
                } else {
                    console.log(' updated in '+(new Date().getTime() - startDate.getTime())+' ms');
                }
            })
            .pipe(source(path.OUT))
            .pipe(gulp.dest(path.DEST_BUILD))
            ;
    };

    bundler.on('update', rebundle);
    return rebundle();
});

Now first compile takes around 20s and each time I update my file it takes around 800ms. It's just enough time to switch from IDE to my browser.