open-roms

The C64 ROM is typically distributed in 2 files 8 KB each, one called kernal, one basic. This might be misleading, as the C64 Kernal takes about 6.5 KB, and the BASIC about 9.5 KB - some parts of BASIC is therefore placed in the kernal file. This is the main reason you can’t easily use the Open ROMs Kernal file with original C64 BASIC.

But it is still possible to combine them:

Unfortunately, some features will be lost this way - for example, the Open ROMs DOS Wedge is BASIC based, so it won’t be available in the hybrid ROM.

Sorry, no Windows support (but it should work under Windows Subsystem for Linux if GCC and libpng devel packages are installed), and no macOS support (I don’t have a machine to test).

Please note, that it is illegal to distribute such a hybrid ROM: