Not a studio, this is development like it's the 90s. Though development is easier now with modern tools, but just like the 1990s it's something one person can write.
the gallery site is amazing in and of itself. the gallery isn't PNGs or GIFs - it's generated in the browser from the emulator state. if you hover over an item it resumes the emulator.
Posts aren't limited to an arbitrary length in activity pub, this is the same UI logic for showing a thread in the main feed. Twitter does something similar for bluecheck long posts.