--- title: "This week's JavaScript news, issue 239" publication: "JavaScript Weekly" issue: 239 published_at: "2015-07-03" canonical_url: "https://javascriptweekly.com/issues/239" --- This week's JavaScript news, issue 239 Eich on WebAssembly, TCO, native vs Underscore, a look at React's performance, and more. — [Read this e-mail on the Web](http://javascriptweekly.com/issues/239) JavaScript WeeklyIssue 239 — July 3, 2015[Why We Need WebAssembly: Interview with Brendan Eich](https://medium.com/javascript-scene/why-we-need-webassembly-an-interview-with-brendan-eich-7fb2a60b0723) Eric Elliott discusses the details of the recently announced ‘WebAssembly’ with JavaScript’s creator. Eric Elliott [Tail Call Optimization in ECMAScript 6](http://www.2ality.com/2015/06/tail-call-optimization.html) Axel goes into some depth to explain what TCO is, how ES6 offers it, and what benefits it provides. Dr. Axel Rauschmayer [You Might Not Need Underscore](https://www.reindex.io/blog/you-might-not-need-underscore/) A look at performing typical Underscore supplied operations using native ES5, ES5.1, ES6/ES2015 and ES7/2016. Reindex [![Frontend Masters\](https://copm.s3.amazonaws.com/3fe9409a.png)](https://frontendmasters.com/workshops/?utm_source=javascriptweekly&utm_medium=email)[A Week of Full Stack JavaScript Workshops](https://frontendmasters.com/workshops/)Build full stack apps in JS with Scott Moss: - [2-Days on Angular, Components and ES6](https://frontendmasters.com/workshops/angular-components-es6/) - [3-Days on API Design in Node.js](https://frontendmasters.com/workshops/api-design-nodejs/) _Join us (all or part) of the week July 20-25th!_ Frontend MastersSponsor [Breakouts: The Same Game on Numerous JS Game Engines](http://www.jsbreakouts.org/) A sort of gamedev answer to [TodoMVC](http://todomvc.com/) where the same Breakout game is implemented on 12 different JavaScript game frameworks so you can compare them. Matt Greer [Small Modules: Tales from a Serial Module Author](http://dailyjs.com/2015/07/02/small-modules-complexity-over-size/) “LOC is pretty much irrelevant. It doesn’t matter if the module is one line or hundreds. It’s all about containing complexity.” Sindre Sorhus [JavaScript Transformation](https://www.youtube.com/watch?v=rKuNbEwoQfQ) Sebastian McKenzie, creator of Babel, gave a talk at JSConf on how JavaScript transformation and ES6 can help improve developer workflow and how it can futureproof your code. JSConf [The Magic of Automated Accessibility Testing](https://www.youtube.com/watch?v=-XUmf_RPF8k) Angular core team member Marcy Sutton talks about testing accessibility automatically using JavaScript in just 30 minutes, but will she get the pizza she ordered? Marcy Sutton [React + Performance = ?](https://aerotwist.com/blog/react-plus-performance-equals-what/) Google’s Paul Lewis noodled with React to see how it held up performance wise and noted ‘for mobile there’s a remarkable cost to using React over not doing so, and the cost is so high as to be reasonably prohibitive.’ Paul Lewis [React v0.14 Beta 1 Released](http://facebook.github.io/react/blog/2015/07/03/react-v0.14-beta-1.html) With 0.14, the main ‘react’ package is splitting into two: react and react-dom. The way DOM references are exposed is also changing. Facebook [A Look at ES6 Feature Performance](http://www.incaseofstairs.com/2015/06/es6-feature-performance/) A look at the performance implications of using ES6 (the next version of JavaScript, essentially) specific features. Kevin Decker Jobs - [JavaScript Engineer — London UK — Improbable.io](http://grnh.se/hjt2pk?utm_source=javascriptweekly&utm_medium=email)Making understanding complexity an intuitive practice. Building out a suite of applications giving the world access to our core simulation technology. Develop tooling, lead framework / library selection develop large scale, high performance apps. Improbable.io - [JavaScript Developer at Backbase (Amsterdam)](http://www.jobscore.com/jobs2/backbase/lead-frontend-developer/aD_iK8ROWr45y7eJe9fLhG?ref=rss&sid=68)Unique fast growing startup - like company, powerful software products, awesome international peers. Come work with us in Amsterdam! The momentum is here now. No BS, just watch it: [Working at Backbase](https://www.youtube.com/watch?v=dvK3JiEv1zg=youtu.be) Backbase - [Apply to the best startups in SF NYC in 60 seconds](https://underdog.io/?utm_source=javascriptweekly&utm_medium=7_3_2015_javascriptweeklysponsor&utm_campaign=weareexclusive)One of every two companies that attempt to join Underdog.io is turned away. Apply as a candidate, and founders hiring managers email you directly. No middlemen no placement fees for companies. Underdog.io In Brief [A Ranking of The 10,000 Most Popular JavaScript Projects on GitHub](http://stats.js.org/) news JS.org [Free Angular 2.0 Webinar on July 22](http://go.rangle.io/angular2webinar) news Learn to write Angular 1 code today so it is easily converted to Angular 2 tomorrow. Rangle.io's CTO Yuri Takhteyev on how to survive the transition. [Register Now.](http://go.rangle.io/angular2webinar) RangleSponsor ['Looks like Apple Music is an Ember.js app.'](https://twitter.com/tomdale/status/616935408786538496) news Tom Dale [Marvell Brings JavaScript To The Smallest Devices Ever](http://www.inserthtml.com/2015/06/marvell-brings-javascript-to-the-smallest-devices-ever/) news InsertHTML [Recursion in Functional JavaScript](http://www.sitepoint.com/recursion-functional-javascript/) tutorial M. David Green [Styling Angular 2 Components](http://blog.thoughtram.io/angular/2015/06/25/styling-angular-2-components.html) tutorial Pascal Precht [Running Arbitrary JS Functions on AWS Lambda](https://alexcsantos.wordpress.com/2015/06/27/running-arbitrary-functions-in-aws-lambda-node-js/) tutorial Alex Santos [A Quick Look at Async Control Flow](http://kaye.us/javascript-async-control-flow/) tutorial With a particular focus on new ES6 patterns and ES7’s ‘await’. Kenny Kaye [Introduction to the Fetch API](http://www.sitepoint.com/introduction-to-the-fetch-api/) tutorial Ludovico Fischer looks at the Fetch API (supported in the latest Chrome, Opera and Firefox), a tidier replacement for XMLHttpRequest in most situations. SitePoint [How to Convert Angular 1 Directives to Angular 2](https://www.youtube.com/watch?v=yHZOu_n5M0Q) video Max Lynch [Async Programming in ES7](https://www.youtube.com/watch?v=lil4YCCXRYc) video A look at some of the proposed asynchronous programming features for the next version of ECMAScript. Jafar Husain [Componentize Your App with Polymer Elements](https://angularu.com/VideoSession/2015sf/componentize-your-app-with-polymer-elements) video Rob Dodson [Doubling Down on npm](https://roost.bocoup.com/blog/doubling-down-on-npm/) opinion A look at moving from using both npm and Bower to just npm. Mike Pennisi [Over The Edge: Web Components Are An Endangered Species](http://christianheilmann.com/2015/07/01/over-the-edge-web-components-are-an-endangered-species/) opinion “I always loved the idea of Web Components [..] However, in four years, we haven’t got much to show..” Christian Heilmann [How Fast Are Web Workers?](https://hacks.mozilla.org/2015/07/how-fast-are-web-workers/) opinion Mozilla Hacks [Spectacle: A React.js Presentation Library, Write Your Decks in JSX](http://projects.formidablelabs.com/spectacle/) tools Formidable Labs [Start Managing Your JavaScript Logs Prevent Errors For Free](https://www.loggly.com/javascript-weekly/?utm_source=javascriptweekly&utm_medium=email&utm_campaign=2) tools Discover how you can find the root cause for specific JavaScript errors before they become problems. Start free. LogglySponsor [ES-Checker: See How Much of ECMAScript 6/2015 Your Browser Supports](http://ruanyf.github.io/es-checker/) tools Ruan YiFeng [cellauto.js: Library for Creating Cellular Automata Simulations](http://sanojian.github.io/cellauto/) code There’s a nice set of demos on the homepage to enjoy. Jonas Olmstead [Introducing Moron.js: A New SQL-Friendly ORM](http://www.vincit.fi/blog/introducing-moron-js-a-new-orm-for-node-js/) code If you like this, don't forget about [Node Weekly](http://nodeweekly.com/). Vincit Oy Curated by [Peter Cooper](http://twitter.com/peterc) and published by [Cooperpress](https://cooperpress.com/). Like this? You may also enjoy: [FrontEnd Focus](http://frontendfocus.co/) : [Node Weekly](http://nodeweekly.com/) : [React Status](http://react.statuscode.com/) [Stop getting JavaScript Weekly](*|UNSUB|*) : [Change email address](*|UPDATE_PROFILE|*) : [Read this issue on the Web](http://javascriptweekly.com/issues/239) © Cooperpress Ltd. 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