In parts of Missouri ten years back, we used paper ballots that were fed into a reader/ballot box combo. Each precinct could take each box/reader and submit the totals at the close of voting. Each box was sealed and was available with the original ballots locked inside for a recount if needed. Elections were at 99% in three hours in almost all situations.
All you really need is a contingent of precinct workers who can read and count. Do it in pairs, with each person from a different political party. It’s been done for centuries. Pretty hard to cheat.