Sloop
(i didn't know where else to write this so i'm dumping this info here).
sloop is nintendo's gba emulator for the switch.
the roms included are lz4 compressed. specifically with these params lz4 rom -9 --content-size
you can repackage any rom you like and change the compression level to whatever. there's no checksums with both the compressed / uncompressed roms. you can also replace the .png files. the size of the png files dont seem to matter either.
another thing that doesnt matter is the save type per game. ie, some games are eeprom, others are sram etc. you can overwrite an eeprom game with a sram game without any issue, so it doesnt look like sloop uses a lut for the save type.
to add new games, you need to add a new entry in the .titlesdb file. ideally, someone (that isn't lazy like me) will write a nice gui wrapper around adding new entries.
here are some tests i ran for accuracy testing. overall, sloop does very well. good job nintendo!
