Funny, I googled "programmer testifies..." and the first autocomplete was "...about rigging elections": https://www.youtube.com/watch?v=tjvtSquZkhs

Journalist Greg Palast also has evidence of electronic voter in Ohio in 2004. (Disclaimer: I have not delved deep on his claims, but the mere fact of their plausibility is deeply concerning.)

http://www.gregpalast.com/how-they-stole-ohio/