I'm looking for feedback on this API. It isn't yet supported in any standard or browser. In the very early days of service workers (while they were still named "navigation controllers") we had the idea of a declarative router. This provided a high-level API to define the behaviour of particular routes, so the service worker wouldn't need to be started. We dropped the idea because we didn't want to
![A declarative router for service workers](https://cdn-ak-scissors.b.st-hatena.com/image/square/275edb50d473e8e4acd3a8035eef743809f96ee2/height=288;version=1;width=512/https%3A%2F%2Fjakearchibald.com%2Fc%2Ficon-d166b7f8.png)