Sequioa Vote Systems (and Smartmatic) which is now Dominion

The AVC Advantage contains a computer. If someone installs a different computer program for that computer to run, it can deliberately add up the votes wrong. It's easy to make a computer program that steals votes from one party's candidates, and gives them to another, while taking care to make the total number of votes come out right. It's easy to make this program take care to cheat only on election day when hundreds of ballots are cast, and not cheat when the machine is being tested for accuracy. This kind of fraudulent computer program can modify every electronic "audit trail" in the computer.

https://wikileaks.org/wiki/Injuncted_Princeton_voting_machine_report:_Insecurities_and_Inaccuracies_of_the_Sequoia_AVC_Advantage_9.00H_DRE_Voting_Machine,_17_Oct_2008