UTW 2025

Tutorial
Internationalization ICU/CLDR

Getting Started with ICU4X

Shane Carr

on  Tue, 14:00in  for  90min

At the intersection of human and computer languages, internationalization (i18n) continues to play a pivotal role in modern software. Evolving i18n libraries means better quality experiences, improved performance, and support for digitally disadvantaged languages.

ICU4X is Unicode’s modern, lightweight, portable, and secure i18n library. Built from the ground up, its binary size and memory usage footprint is 50-90% smaller than ICU4C. It is memory-safe, written in Rust with interfaces into C++, JavaScript, TypeScript, Dart, and more in the pipeline. Mozilla Firefox, Google Chrome, Google Pixel Watch, the Android operating system, numerous Flutter apps, and more clients are already using ICU4X.

In this tutorial, you will learn when ICU4X is the right tool for your i18n, and you will learn how to integrate ICU4X into your code base. This will be an interactive session, so come ready with a laptop to code in either a native environment or in JavaScript.

 Overview  Program