These days, having enough unit tests for a JavaScript-based web application/library is the bare minimum. Ideally, the code coverage of those tests is also monitored in a day-to-day development situation. Fortunately, this is easy to do with a modern test runner such as Venus.js.

A few days ago, I gave a talk at the most recent Web Tech Talk meetup hosted by Samsung. The title is Supersonic JavaScript (forgive my little marketing stunt there) and the topic is on changing the way we think about optimizing JavaScript code.

One of the interesting features of Esprima is to retrieve every comment inside a JavaScript source. Even better, each comment can be linked to the related syntax node. This is very helpful (like in the case of JSDoc) since any additional information regarding the program can be provided via the comm...

The most recent Java 8 release came with lots of new features, one of them is the brand-new JavaScript engine to replace the aging Rhino. This new engine, called Nashorn (German for rhinoceros), is high-performant and specification compliant. It is definitely useful whenever you want to mix-and-matc...

The tagline of this blog: Don’t code today what you can’t debug tomorrow.

Eclipse Orion released its latest version 5, right before the most recent EclipseCon. This new version packs several exciting features, everything from stylistic change in the appearance to an streamlined cloud deployment. My favorite is the easy-to-use Node.js bundle.

This week it’s all about the most recent Fluent Conference 2014 in San Francisco. It’s the third Fluent and boy, it’s getting more phenomenal than ever.

While static polymorphism is often discussed in the context of C++ (in particular, related to CRTP and method overloading), we can generalize the concept to help us choosing the most optimal function and property names of a public interface. This also applies to JavaScript API, of which some example...

Extracting a portion of a string is a fairly well understood practice. With JavaScript, there are three different built-in functions which can perform that operation. Because of this, often it is very confusing for beginners as to which function should be used. Even worse, sometimes it is easy to fa...

In the last two days I have been busy with DevNexus 2014, the largest tech conference held in Atlanta. DevNexus has been going on for a while and this year it’s getting really big with over 1,000 attendees and tons of speakers.

The use of graphics processing unit (GPU) in modern browsers, particularly for page rendering, means that there is no more excuse for laggy animation. In some cases, when the intended animation is not necessarily GPU friendly, some tricks need to be employed so that the graphics operations do not ca...

The amazing weather in San Diego became the witness of the awesome jQuery Conference held this week. The keynotes were entertaining, the talks were inspiring (the videos will be available in the near future), and of course nothing beats meeting folks from this vibrant jQuery community.

In JavaScript, mistaking slice for splice (or vice versa) is a common mistake among rookies and even experts. These two functions, although they have similar names, are doing two completely different things. In practice, such a confusion can be avoided by choosing an API that telegraphs the const-co...

At the recent San Francisco JavaScript meetup, I gave a talk on the subject of Searching and Sorting without Loops as part of its Functional Monthly series. In that talk, I explained various higher-order functions of JavaScript Array and their usage to replace explicit loops (for or while) in severa...

Many free/open-source projects often suffer from a very specific feedback where it is assumed that a certain feature will not be implemented because of a philosophical reason. It is what I called as the “flying car” problem.

Three years ago, the first version of PhantomJS was announced to the public. It is still a toddler, but hey, it is growing up and getting some traction at an unprecedented rate.

How does your engineering organization build and deliver products to its customers? Similar to the well-known capability maturity model, the maturity level of a build automation system falls into one of the following: chaotic, repeatable, defined, managed, or optimized.

In the fifth part of this JavaScript kinetic scrolling tutorial, a demo of the attractive Cover Flow effect (commonly found in some Apple products) using the deadly combination of kinetic scrolling and CSS 3-D will be shown. The entire logic is implemented in ~200 lines of JavaScript code.

In the first part, I showed you an easy way to test PageSpeed Module by running it as a proxy, thanks to nginx and ngx_pagespeed. Instead of a prebuilt binary of PSOL (PageSpeed Optimization Library), this second part demonstrates how to build it from source.

The fourth part of this JavaScript kinetic scrolling series shows an implementation of horizontal swipe to browse a gallery of photo. In addition to that, a simple parallax effect will be demonstrated as well.

Many JavaScript projects are using Mocha to run the unit tests. Combining Mocha with Istanbul and Karma, it is easy to track the code coverage of the application code when running the tests.

PageSpeed Module from Google, available for Apache and nginx, is a quick solution to improve web application network performance. As a bonus, if we configure nginx as a proxy server, then it can also serve as a web acceleration solution.

In the third part of this JavaScript kinetic scrolling series, the so-called snap to grid feature is demonstrated. The implementation is rather straightforward, it is a matter of figuring out where the scrolling should stop and then adjusting that target position to the intended location.

It is getting colder, it starts to feel like winter. Right when it will be warmer again slowly, it is time for me to give another round of tech talks.

In the second part of this series of JavaScript kinetic scrolling example, the inertial effect is implemented. This is done by tracking the movement while the user is still dragging the view and then automatically scroll the view until it stops at some point.

Nexus 5 is the most recent high-end smartphone with the authentic Google experience. With its amazing performance at the given price, Nexus 5 enjoys favorable reviews from The Verge, Ars Technica, ZDNet, Engadget, ComputerWorld, and many others. In term of web browsing experience, how does it compar...

The process of managing a virtual machine is heavily simplifed via the use of Vagrant. However, there is still a manual or a semi-automatic process involved for creating the base box itself. There are many tools designed to solve to this problem, the most recent one is Packer from @mitchellh, the ve...

Last week I started a new chapter in my professional career. I am now working for Shape Security, a cool startup in Mountain View focusing on the next-generation web content security.

With my new partner-in-crime Ann Robson, we had a presentation JavaScript Insights at the most recent HTML5 Developer Conference in San Francisco. In this talk, we discussed several important JavaScript code quality tools.

An implementation of a sorting algorithm usually uses one or more iterating loops in the form of for/while statement. With JavaScript and its powerful Array object, these loops can be avoided since Array’s higher-order functions are enough for iterating the array. One candidate for this technique is...