Service workers are limited though. A site can opt to perform whatever substitutions it likes, but it can only do that for its own requests.

node aesthetic.

We use @Caolan's excellent Async library. Our code is not 5 level deep nested callbacks. We currently have about 45,000 lines of Javascript in our main repository. In this code base, we have used the async library as our only flow control library. Our current use of the library in our code base: async.waterfall: 74 async.forEach: 55 async.forEachSeries: 21 async.series: 8 async.parallel: 4 async.queue: 3 I highly suggest, that if you are unsure about Node.js and are going to do an experiment project, make sure you use Async, Step, or one of the other flow control modules for your experiment. It will help you better understand how most larger Node.js applications are built.

We decided to make a spreadsheet of the possible environments we would consider using for our next generation product. The inputs were: Community Velocity Correctness (aka, static typing-like things) Debuggability/Tooling Downtime/Compile Time Libraries (Standard/External) Testability Team Experience Performance Production We setup the spreadsheet so we could change the weight of each category. This let us play with our feelings, what if we only cared about developer velocity? What if we only cared about testability?