Hello HN friends. I am here for a long time reading high quality content. Now is my time to ask advice.

I have a freemium SAS software with a good number of visitors. Its free to use, but the API is paid. It solves a problem of a small niche industry. I already have a dozen of paying customers, and it already pays my rent. The retention is very high, but the growth is very slow. I am able to sell, but I see that I need to make some efforts on marketing. How can I do marketing for such a small niche? I already did SEO (and continuously do) and I have a good traffic of search engines.

For this kind of business, I can think only in "content marketing", even being very technical an niche, and because I can't see other better solution, I shall spend some time doing it. As marketing is not my area (but I like and read a lot) I am afraid of spending too much time on this being blind of another better strategy, so I am here to ask:

Anyone has books or advice for my challenge? Anyone have seen similar cases, sharing the characteristic I mentioned (Small niche, freemium, SAS, B2B, API paid, global market)?

Obrigado (thank you).