Ask HN: Is it ok to place an ad for my startup in my OSS?

I would move the project to be under the company instead of your personal account. Place links back to the company on the package website. Link back to your company in the terminal output. I wouldn't go beyond that.

I think it is fine if it is unintrusive and properly labeled.

If you are launching a paid serverless SAAS service and it is useful to the audience who are using your project, then you can put at the top otherwise I would go for bottom.

Well, I wouldn't mind to see that ad, if it's done tastefully. It's just, I would also think that you are not capable to run a real ad campaign, which in turn would make me loose trust in your business. If you can't run ads, what else is running wrong in your shop? Thus then never consider your product at all, ever.

Even this question should be done anonymously, IMHO, now you just publicly announced that you don't know what you are doing in terms of PR and marketing for your cool product.

I would advise against it. Advertising has known bad effects, and practitioners end up getting lured to the dark side over time.