Ballotix: A Practical Mixed Code Receipt Protocol Achieving Full Coercion Resistance in End-to-End Verifiable Voting

This paper presents Ballotix, a practical end-to-end verifiable voting system that resolves what we term the Election Impossibility Triangle-the challenge of simultaneously achieving verifiability, ballot secrecy, and coercion resistance. Existing systems such as Estonia's i-voting and ElectionGuard achieve at most two of these three properties. Ballotix introduces the Mixed Code Receipt Protocol, in which each voter's receipt contains their verification code hidden among real codes from other voters, making the receipt verifiable but incapable of proving candidate choice to any third party.

Combined with a plain-text SHA-256 hash chain ledger and optional automated camera verification for remote voting, Ballotix provides a complete, transparent, and practically deployable solution. A working prototype is available at ballotix.org.