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Presentation: JS � Character Encodings

Track: JavaScript: Pushing the Client Beyond the Browser

Location: St James, 4th flr.

Duration: 5:25pm - 6:15pm

Day of week: Monday

Slides: Download Slides

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What You’ll Learn

  1. Hear about some of the issues existing with character encoding in JavaScript.
  2. Learn how to avoid some of the common mistakes with character encoding in Node.js and web development.


Character encodings can be confusing for every developer, providing pitfalls even for the most experienced ones, so a lot of the time we want to end up with something that “just works” without an in-depth understanding of the involved concepts. In this talk, Anna will give an overview over what they are, what the JavaScript language provides to interact with them, and how to avoid the most common mistakes in Node.js and the Web.


What is the focus of your work today?


I work on Node.js. That is pretty much my job description. I get to work on the core software, on the platform itself. There have been two parts that I've been working on. One is our test suite, it has a couple of flaky tests, which can be annoying, and I’ve been trying to fix some of them. The other thing is something that I pushed forward a lot, namely bringing Workers along the lines of Web workers to Node.js. While the feature is stable now, and has been for a while, there's still a number of things that we do: improving documentation, improving performance, and working out some really weird edge-case bugs.


What is the motivation for your talk?


I realized that the talk is a bit off for such a conference, it's not about bleeding-edge features, it is very technical and it is about problems that have been around for a while. But it's still something that I'm passionate about. I have given talks about this general topic, about character encodings and how they work in JavaScript, a while back, a couple of years ago at smaller conferences. One motivation for this is that we keep getting issues around encoding issues on the Node.js GitHub issue trackers: It's just something that people tend to keep messing up.


How would you describe the persona for your target audience?


The target audience is definitely developers. I would consider it an intermediate talk, but also targeted at beginners: When it comes to things like encoding issues, in my experience beginners might be people that want to get things to  “just work”. But once things just work, they tend to stop diving deeper into these issues.

Speaker: Anna Henningsen

Node.js Developer

Node.js core developer @NearformResearch

Find Anna Henningsen at

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