I wrote this a while back to switch away from my old Google Maps based minimaps viewer as Google Maps no longer met my requirements.
This code is currently used for hosting https://newmaps.marlam.in, which is regularly updated with new minimaps when Blizzard pushes patches.
Minimap extraction, compiling and processing aren't part of this repository but might be in the future.
Many thanks to @xPaw for his help with this project.