Is there a HN API that allows you to post comments/stories too (not just read)?

Basically, I want to create a web-based HN App which both fetches the user's posts/comments & allows them to post them.

I know that the standard APIs available on Github (Firebase) and Algolia are good but they are read-only. Do you know of any other API which has a POST/PUT interface for posting comments too?

On the play-store, I found this app authored by another dude, wonder how he's able to do it?

https://play.google.com/store/apps/details?id=io.github.hidroh.materialistic

(The front-page of the app says, "Public APIs are provided by Hacker News, Algolia and Readability.")