Letterpub: Substack Newsletter Search Engine

Hello Product Hunt, a lot of people are starting email newsletters but I found it difficult to discover them. The only way to discover newsletters has been to use the main directory on Substack website (which can only feature as many publications) or to discover organically through people who you already follow on social media. It's not easy to find writers who write about topics you care about. Conversely, this is a problem from the writers' point of view as well, because unless you already have a large following, it's very difficult to get discovered no matter how well you write. So I built a Substack search engine. It indexes public newsletters and lets you search by keyword as well as filter by publications. This is version 0 and I am launching as soon as it's functional enough instead of adding tons of features upfront because I wanted to learn what people want and go from there. Try it out, and please let me know if you have any feedback or feature request.