Ask HN: What internal tools/SASS replacements are you building?

I hear more and more from people in companies of all sorts, are building internal tools/replacements of SaSS businesses.

We built an automated QA agent based on Playwright, that does QA on our own products, literally in a week and we continue to contribute to it. Our QA engineers love it.

What sort of things/products are you building?

What are the stats around internal tool building in the last 2-3 years? rates of adoption? are internal users satisfied?