Plik źródłowy wymaga innej solidności wersji kompilatora
1) check what compiler version it requires at top of file
2) will say "0.8.4" or "^0.8.4" or something along those lines
3) if it doesn't have "^" then it has to be that exact version
4) if it has "^" it must be that version or higher
John Appleseed