ConfPad

Venture deep into the belly of the browser to uncover the secret incantations to instantly load anything. We’ll even back it up with rock-hard data. Will we use preload, prefetch and preconnect? What about HTTP/2 Server Push? or Service Worker? and how the heck do we ship JavaScript bundles that don’t break the bank on mobile? Discover this and more tips to …

How can we know how good we’ve got it without really understanding how good we used to have it? JavaScript was first released with Netscape Navigator 2.0 in September 1995 - can an application from today exist in the browsers of yesterday?Just how different was the development experience then compared to now? Is it feasible to implement a modern Web applicat…

Functional programming has been gaining a lot of popularity in the JS community, and with good reason rejecting side-effects and mutability - in-place changes to data - helps avoid a lot of headaches. But when you refuse to mutate objects, you have to create a whole new object each time something changes, which can slow things down and eat up memory, making …

NESpectre is a genuine 8-bit NES videogame console that’s been transformed to accept massively-multiplayer input from an entire audience via our JavaScript stack. Come haunt our NES with your supernatural influence and expect the wildly unexpected to happen! Visual and audio glitches, impossible game scenarios, 100-player versions of classic games and more w…

In 2016, we at The Financial Times launched a new version of our website to great success. It broke ground on key areas in which we’d set out to excel and measured very closely, like performance, resilience and usability. But one day, and rather serendipitously, we realized we had largely forgotten to measure one thing: accessibility. And you can’t improve w…

How did piece of satire lead to a ASCII picture of Guy Fieri getting merged into the Babel source and our t-shirt design? Who is left_pad? How did I go from complete ignorance of one of the biggest tools used in the JavaScript ecosystem to becoming a user, contributor, and eventually maintainer? What are some of the interesting stories that maintaining a pro…

Come and be fascinated by the world of audio visualisation in a browser. This isn’t just about creating stunning data vis to music! We see how we can pipe data realtime into custom properties to enhance our visuals. The speaker re-addresses how we analyse sound via the Web Audio API and proposes a better way of processing the data to better suit music. And, …

Research shows that by simply regulating their breathing, one may experience less fear, anxiety, and improve memory. Sure, we all could strive to become more mindful and self-aware, but in true programmer fashion, I ask, “why not use technology instead?” Even better, why not use open-source technology to monitor and alert ourselves of these arrhythmic respir…

Jest was adopted widely across 100s of companies recently and provides an immersive testing experience. We’ll take a deeper look at JavaScript Testing with Jest and what it takes to turn a tool into a product with a delightful experience.

Fade in. An opened terminal window. iTerm2 is the flavour. Dracula, the theme. You split the panes in two. You are at it again a stash of audio buffers and that dream of manipulating a lossless file. With node as your language of choice you embark on the night. You manipulate, you transform, you have your byte order sorted, on their own accord your fingers t…

Rather than just playing videos in the browser; what if you could edit and composite them on the fly?Just as the Web Audio API allowed for dynamic audio manipulation, we can now do similar things for video, opening up the creative possibilities for interactive visual experiences on the web.In this talk I’ll show you how, with some live coded demos using an o…

Every other week there seems to be a new dump of cracked passwords, hurting innocent and unbeknownst users. It seems as if keeping users passwords safe is an herculean task, even beyond the most resourceful organisations. However it doesn’t have to be.Password hashing is a important discipline in cryptography. Securing passwords has become so integral to our…

But it makes things so nice and easy :) AMP at its heart is a JavaScript library for building super fast static web pages. Being purely web tech based, we can understand how it works and take the best ideas and use them in non-AMP projects. This talk will dig into the nitty gritty details of AMP and uncover how the sausage is made so to say. We’ll talk about…

Https is the new normal. We all knew that the CAs are not working properly. The chain of trust between the website and “me” is founded on the believe of the “green lock”. If we dissect this chain of trust we find the “weakest link” the private-key’s. This discovery leads to question how we manage our digital identity. And leave the unanswered question, how c…

Creative expression on the web shouldn’t be limited to people who know how to code. In this talk, we’ll explore how to repurpose the sophisticated tools that designers already know to build interactive, dynamic art on the web.I’ll demonstrate this principle through a JavaScript library that allows designers to create full-bleed animated comics, graphic novel…

Did you know that how we learn JavaScript has changed a huge amount over the last ten years? Lots of small changes in how we introduce people to JS have built up over time into a radical difference - these changes are based in sociolinguistics!Our community’s communication has evolved rapidly. We’ve moved from only valuing the opinions of senior developers t…

Making art on the web is easy, if you got the right tools. HTML has styled divs. JavaScript has canvas. I have an emoji keyboard. But what if our tools were better, and making art was easier? What if there was a magical widget that transformed any word into emoji word art? Or an image into pixels, which you can then style with CSS? What if it was easy to bui…

Two web developers who are full of curiosity to learn all about machines and code met at a meetup. Unsatisfied with traditional computer science textbook and what we felt like not so learner friendly software engineering landscape, we decided to learn by working together in the format we enjoy the most - creative project.We are building machines (both softwa…

Breaking the API of a package can create severe disruptions downstream, but package maintainers have flexibility in whether and how to perform a change. Through interviews and a survey, we found that developers within a community or platform often share cohesive practices (e.g., semver, backporting, synchronized releases), but that those practices differ fro…

“MAKE IT MODULAR,” they said. “IT WILL BE BETTER,” they said. Modularity is a term so common in today’s software industry, that it’s easy to uncritically accept it as a fundamental software development principle. but what does “modularity” actually mean? Where does this idea come from? Where is it going? This talk will walk us through the technical etymology…

Today’s most popular frameworks come from a time when the world was a different place. Ember’s first rendering engine, for example, was optimized around the performance gotchas of Internet Explorer 6. IE6 has since faded into history, and smartphones with spotty connectivity and occasionally dodgy hardware have become the lowest common denominator that we mu…

The early 2000s bred a new generation of web developers and designers out of the pure need of creative expression. Teens didn’t have access to StackOverflow, and couldn’t easily Google their coding problems—so they turned to each other. Through collaboration and inspiration from others that were blazing their own way, they created their own unique personal s…

Over a year ago, the nested loops opened jsconf.eu 2015 with their debut single (and only song to date) “Javascript, what are you?”. Buttons were pressed, videos were played and music was heard, but nobody was really sure what even happened.And we want to answer the simple question. “How is it made?”. We’ll show you why and how Javascript and a lot of other …

Jet Propulsion Laboratory - scientific institution making research and development for NASA. Their portfolio includes such famous missions as Curiosity Mars rover and Voyager probe which left solar system after 25 years of flight and still providing scientific information. High level of automation and long duration of missions led to superior demands to soft…

Today’s Javascript developers are working at an intersection of user experience, security, and the next generation of connected technologies. With the growth of full-stack JS tools and the expansion of the Internet of Things, robust Javascript applications will play an even bigger role in the devices and tools we use every day.With this great power comes an …

Want to know how JavaScript engines work? Why is JavaScript so fast? What is just-in-time compilation? We’ll look at basic concepts of compilers, challenges posed by modern JavaScript, and how to write compiler-friendly JavaScript.

JavaScript is notoriously bad when it comes to date and time problems. The built-in Date object has so many quirks and implementation differences that many developers have abandoned it, in favor of libraries. How did we get here, and what can be done about this? This talk is in three parts, and led by maintainers of the Moment.js library. First, you’ll under…

Parsing JavaScript fast is critical for fast web page startup. We’ll look at challenges posed by complex frameworks and new language features and how V8, the JavaScript engine behind Google Chrome, solves them. You’ll learn how to write and bundle your code in a way that is fast to parse.How does V8 parse JavaScript and how does it decide what parts to parse…

You’re probably familiar with source maps – they let you debug your original, unminified and untranspiled code in the browser. But ever wonder how they actually work? In this talk, we deep dive into the source map format to see what’s under the hood. We’ll cover source map generation tools and parsers, and learn how to manipulate source maps directly for fun…

The Internet of Things is quickly entering our lives with stunning feats of innovation–and sometimes absurdity. Internet connectivity in household and industrial devices truly holds a great deal of promise, but is the pace of innovation too fast and is the design praxis sufficiently rigorous? Is JavaScript well-suited to control devices that can cause materi…

Do you feel limited, boxed in, like you are unable to grow? Try to imagine how numbers in JavaScript feel - they are stuck between +/- 9007199254740991. Unable to breathe, they are stuck.I will talk about how we can free numbers in JavaScript to represent values much larger than their natural constraints. The talk will navigate through increasingly creative …

WebAssembly is fast. It’s being called “the future of the web”. It’s speed and potential have major browser vendors working together to make it a reality. And it’s on it’s way—the MVP hit multiple browsers in October of last year.But what makes it fast? Starting from the basics, this talk will walk you through what WebAssembly is, and then why it’s fast.

Every time I have to check the “Male” or “Female” boxes, it feels :poop emoji:. By building and shipping expanded gender options at my $DAYJOB, I learned how to convince folks that gender options in product matter, how to get time and resourcing for social justice projects at work, and how to measure the success of a feature that only a small portion of user…

For a language originally created in 10 days it surely has a lot of quirks and perks many JS developers are unaware of. Sometimes, it might even seem like we fell down the rabbit hole only to find that NaN is actually a Number, undefined can be defined, +!![] equals 1, Array.sort() may not work as you suspected and so much other nonsense that can trip any JS…

Do you want to show your caring for the JavaScript community by doing some sharing? At work, are you thinking that the code you keep pasting in project after project should become an internal library? The key to creating a great library is designing an API that people love using. We will walk through API design patterns in popular JavaScript libraries, inclu…

Front-end developers sit atop a massive amount of technology, often treating whole pieces of our application as opaque functionality. Grab a hard hat and follow me down into the internals of Preact, a tiny 3kb alternative to React. Along the way we’ll shed light on fundamentals like JSX & Virtual DOM, demystify DOM diffing, and see how keys work up-close. On…

The vast majority of website owners (and therefore JavaScript users) are non-technical. They don’t know how to copy-paste an embed code, much less how to use ES7 or React. But these website owners have a right to the same high quality tools we use every day.By building tools which can be dropped into pages, which learn their configuration from their environm…

Every talk you’ll hear about ‘web performance’ will tell you that shaving 100ms from response time produced a 1% sales yield for Amazon, or maybe that 40% of web visitors will abandon your site when it takes more then 3 seconds to load? While those are impressive, there are some more interesting metrics that we need to talk about.Did you know that 43% of the…

There’s an old software joke that goes: “Some people, when confronted with a problem, reach for regular expressions. Now they have two problems.” Regular expressions are a web developer’s best friend and worst nightmare. Sure, you’re glad someone posted the regex pattern for a phone number on Stack Overflow, but when the intern asked you to explain what a “c…

We’re accustomed to great connectivity but what if you need to access important info when you’re disconnected? This session will uncover the approaches used in successful real world examples of Offline First and show you the tools and techniques that will allow you to build the same kinds of things. From supporting hospitals in Africa to providing electric p…

Of course you know what beautiful code looks like. Too bad nobody actually agrees with you. So, what exactly makes beautiful code? Is it readability? Elegance? Simplicity? How much of it depends on the programming language, on your coding style and on the actual code you’re writing? The presentation will contain nothing but code and thus the talk will be lar…

In a few months time, I had created a new calendar for our partners at Booking.com. Months? Yes, months. Creating a calendar that works correctly all across the world for 42 different languages and even more locales, is not something that you do in a week. In this talk I will talk to you about the weird things I learned. From Brazilian Summer Time and Slovak…

Early look in to the upcoming JavaScript features SharedArrayBuffer and Atomics. I will show you, how to craft complex applications using shared memory and gain massive performance boost by utilizing all available CPU cores for parallel computation on same data. I will also teach you how to write safe code while using shared memory and avoiding deadlocks of …

August 30, 2016, was by all accounts an average Tuesday, and release number 523 just a simple re-factor, but something went horribly wrong that day bad code escaped from the office, and it quickly spread to infect tens of thousands, giving rise to a hoard of zombie ServiceWorkers!This is a disaster about a typo. This is a thriller about technology out of con…

JavaScript Style Sheets (JSSS) was a technology introduced by Netscape in 1996. Chances are, you’ve never heard of JSSS, since it was available in Netscape Communicator 4.0. They allowed you to define custom styling rules for your web pages. You’re probably more familiar with its competitor at the time—CSS. They were pretty cool though. JSSS allowed the deve…