The guidelines [1] state:
>Please submit the original source. If a post reports on something found on another site, submit the latter.
>Please don't use HN primarily for promotion. It's ok to post your own stuff part of the time, but the primary use of the site should be for curiosity.
>Don't solicit upvotes, comments, or submissions. Users should vote and comment when they run across something they personally find interesting—not for promotion.
(They solicit upvotes in their slack/twitter/etc)