Ask HN: One-person startups/SaaS that are profitable?

Hi, I was wondering as I am starting startup, are there here any one person startup/SaaS? And how do you manage marketing/sales/development, as I feel those are completely different skill sets.

Edit: If anyone is wondering my MVP is: https://sentimentscanner.com/- google play analytics/statistics/reports of comments by chatgpt Edit2: I was inspired by https://news.ycombinator.com/item?id=21332072