Ask HN: How to get your open-source project gain popularity?

If someone has made a free-to-use tool that is open-source and legitmately helpful (and not AI slop). How do I get it to people?

I have already posted it here on HN, on subreddits, on LinkedIn, and some forums. Where else can I post (for free)?

What other social media platforms would be good for this?

For context I have two tools: one is robotics related and the other is ML related.