Maybe simpler? When open the DB, change it to WAL mode, turn off the automatic checkpoint https://www.sqlite.org/pragma.html#pragma_wal_autocheckpoint https://w

Maybe simpler? When open the DB, change it to WAL mode, turn off the automatic checkpoint https://www.sqlite.org/pragma.html#pragma_wal_autocheckpoint https://www.sqlite.org/pragma.html#pragma_wal_autocheckpoint When user saves, you just checkpointing the file, merging it back into the main database.