Typescript not actually doing anything

[flibbles]

Am I going insane?

This whole project is using typescript, but it's not actually type checking anything. I can put this right in the middle of the echarts widget:

function test() : string {
    return 5;
}

and nothing gets called out when I build. And it's not just being optimized out. I can make changes to existing methods to mess up their types. No compile errors.

Am I doing something wrong? I'm running these builds through npm run publish and such.