Metamorphosis doesn’t have to be ugly: forget about Kafka or what a butterfly has to go through before it shows its amazing apparel. Angular 4 has evolved for you and is showing its best colors. “Just how different is it from Angular 2?”, you might wonder. There are some overall and package-specific changes, as well as new features.
First of all, it is smaller and faster (source) — the butterfly has abandoned its cocoon stage and has a lot more to offer. Besides, AOT generated code is looking more attractive: it’s much slimmer (about 60% less than before). What does this mean for you, the developer? The more complex your template work is, the more you save in terms of time and effort, as well as production bundle size — we’re talking hundreds of kilobytes (source).