Application Development

TypeScript

JavaScript with type checking for safer changes

Maintained by

Microsoft

Released 2012

Source code and version control tooling on a developer screen

Plain explanation

What TypeScript is

TypeScript is JavaScript with a type checker layered on top. You describe what shape your data is supposed to be, and the checker flags mismatches while the code is being written rather than after it reaches production.

JavaScript with static type checking. We use it to make larger browser and Node.js applications easier to maintain and safer to change.

How Axis uses it

We write nearly all JavaScript work in TypeScript. On business systems that live for years, catching a broken data assumption at build time is far cheaper than catching it in production.

What it is used for

Where TypeScript shows up in our projects

These are the practical applications we build with it, not a list of everything it can theoretically do.

React applications

Node.js APIs

Shared front-end and back-end models

Large business applications

Long-lived software products

Honest assessment

When TypeScript is the right call, and when it is not

Every technology has a range where it performs well and a range where something else is a better answer. We would rather say so up front.

A strong fit when

The codebase will be maintained by more than one developer
Data shapes and API contracts need to remain consistent
The project is expected to grow in features and complexity

We would consider another option when

A very small one-off script does not justify a compiled project
The runtime or existing codebase is intentionally plain JavaScript and migration value is low

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