1 - install golang from golang.org for your platform
2 - download repo
3 - run go build .
4 - have chdman from the MAME project installed somewhere in your path.
Try it in a test folder first. Program will unzip any .zip files, and convert the ISO or CUE/BIN files in it to CHD using chdman.
I am not responsible for any loss of data. Use at your own risk.