Hacker News Reader

It looks like this library does use es6 features and requires babel to build from source.

Not required. You can just include the pts.js or pts.min.js in script tag. https://unpkg.com/pts@0.5.0/dist/pts.js

He said building from source, not using an already built version. For that you need babel.

You're right. Sorry I misunderstood.

Typescript is compiled with tsc, not Babel. The npm package includes built Js and original ts