It is often said that we should choose the right tool for the job. When we want a language that doesn’t crash at runtime, we often think of Rust or Haskell. When we want the language to enable speedy delivery, JavaScript comes to mind. But what to choose if we want both type-safety and speedy delivery? This talk will show that in such a scenario TypeScript is an excellent bet. Over the years, TypeScript has developed a very powerful type system. One that is on par with languages like Rust, without sacrificing the speedy delivery of JavaScript. It’s still fast to develop the code we want and it’s easy to make it type-safe. I will show how we’ve used TypeScript to match Rust in making programs type-safe and how a form of dependent types (type operators) can even express some constraints that are difficult to express in other languages. This talk will cover *What is so unique about TypeScript *How it allows to make programs type-safe *How easy it is to do so *What the limitations are