Technology
TypeScript
TypeScript is how we keep a site or a SaaS from rotting the first time a new person opens the repo. Types travel from the CMS to the page.
What it is
TypeScript is Microsoft's typed language that compiles to JavaScript. It is JavaScript with a type system: interfaces, unions, generics, and an editor that can tell you a field is missing before a user does. Almost every serious web codebase we open now is TypeScript, even if the runtime is still the browser or Node.
It does not replace JavaScript. It is JavaScript with a compile step and a contract. Teams adopt it so a tenth page does not invent a second shape for a user, and so a rename does not become an archaeology project.
What it does
Product teams use TypeScript for web apps, APIs, design systems, and scripts that have to last. React, Next.js, Node, and Vue all have first-class TypeScript paths. The types are the documentation a new hire can click.
We write it when the product will be kept. We share types across the UI and the API when that saves meetings. We do not add a type circus that hides a simple page.
Why we use it
Typed JavaScript so the product stays changeable.
Shared types for content, responses, and UI props. If a CMS block cannot be published in a broken shape, that failure happens in review, not on the live page. Lint and types sit on the pull request. The README stays short because the types explain the domain.
If the types and the product disagree, the types are wrong, or the product is. We fix that in the same pull request.
Built on it
Microsoft
Created TypeScript and uses it across VS Code, Office on the web, and Azure tooling.
A large share of Angular and of Google's web properties are TypeScript.
Slack
The desktop and web clients are a well-known TypeScript codebase.
Airbnb
Publicly described migrating a huge JavaScript surface to TypeScript.
Shopify
Hydrogen, Polaris, and a large share of new storefront work are TypeScript.
Tell us what needs to ship.
You use a working prototype before the production build goes ahead.