Recently I spent a good part of two working days decoding service workers to make an app work offline. I hope this post clarifies some tricks and techniques for dealing with Cache Storage and Service Worker APIs and saves you some time. function fetch (req : Request) : Promise<Response> Fetch API provides a rich interface for creating…

Promises are a well known solution to the Callback hell problem that arises in asynchronous JavaScript programs. Borrowing some ideas from Functional languages, I am exploring a different approach to address callback hell in this post. …

In this post I’ll present a reusable function for timing async operations in JavaScript. calc is an async function that we like to profile. By convention its last argument is a callback. We use calc like this: calc(arg, (err, res) => console.log(err || res)) Perhaps the easiest way of profiling…

We usually breakdown the traffic of a campaign into its sources: the publishers (apps or websites) which display our ads. Often the quality of traffic from different sources varies. Some sources never convert while some have a few times higher conversion rate than the campaign’s average. We like to detect…