I have a small idea that I'd like to try building, I (probably) can make something usable without any extra readings but I guess I'd rather make something right and smaller than bigger but designed awfully. what are some good textbooks / resources for building a small social media app. Just to clarify, I don't mean "how to use Flutter / RN" etc, I mean, more to do with the system design, sending messages between users, storing data etc