Welcome to our blog! I'm Jason Williams, a senior software engineer on Bloomberg's JavaScript Infrastructure and Terminal Experience team. Today the Bloomberg Terminal runs a lot of JavaScript. Our team provides a JavaScript environment to engineers across the company.Bloomberg may not be the first company you think of when discussing JavaScript. It certainly wasn't for me in 2018 before I worked here. Back then, I attended my first TC39 meeting in London, only to meet some Bloomberg engineers who were there discussing Realms, WebAssembly, Class Fields, and other topics. The company has now been involved with JavaScript standardization for numerous years, including partnering with Igalia. Some of the proposals we have assisted include Arrow Functions, Async Await, BigInt, Class Fields, Promise.allSettled, Promise.withResolvers, WeakRefs, standardizing Source Maps, and more!The first proposal I worked on was Promise.allSettled, which was fulfilling. After that finished, I decided to hel

Source maps are a vital part of modern web development. Today, we have an official standard, a large group of members, and many exciting features in development! But it wasn't always this way.It may surprise you to learn that, for years, there was no official standard describing the source map format. On one hand, it is incredible that for 10 years, bundlers, browsers, and devtools worked together with only a shared Google Doc between them! On the other hand, it became impossible to add new features, deprecate old features, and build the necessary devtools to support dozens of deviations.Why do we need Source Maps? #Web development used to be simple! You’d write a bit of JavaScript, stick it in a <script> tag, and send it to your users. This also made debugging very simple: the code that ran on the website was the exact code you authored.As web development became more complex, tools began to emerge to optimize large JavaScript applications. In 2009, Google released Closure Tools, a sui

Hello, world 👋This is a new blog written by engineers, for engineers. On it, we will be publishing technical content from Bloomberg folk who work on our thriving JavaScript environment. This also includes web/web-adjacent technologies, and it very much includes TypeScript. After all, TypeScript is JavaScript plus types.Why now? A better question is perhaps: why not sooner? For more than 20 years, JavaScript has powered the Bloomberg Terminal, which is used by more than 350,000 financial professionals around the world. During this time, thousands of Bloomberg engineers have shipped more than 10,000 apps, accumulating more than 100 million lines of server-side and client-side JavaScript code. We have a strong interest in maintaining open web technology (as well as the adjacent runtimes and tooling) as a robust, long-lived technology basis for our business. Correspondingly, for over a decade, we've participated seriously in the broader web community through technical contributions to its...