HN isn't a 'platform', indie hackers + product hunt are more 'platforms'... but I think best thing is to put it in all the startup directories, some are paid...

HN isn't a 'platform', indie hackers + product hunt are more 'platforms'... but I think best thing is to put it in all the startup directories, some are paid... whatever your budget allows go all out, and maybe also do a PR blast, and some interviews if you can on major tech blogs, and maybe give freebies to any influencers related to your startup.