  We propose BlockLot, a blockchain based verifiable lottery. BlockLot provides
transparent, immutable, fair, and verifiable lottery services enhanced by
recent blockchain technologies such as append-only (replicated) distributed
ledger and smart contract. In addition, BlockLot allows all participants to
perform various verification to ensure that the system is actually working as
expected. We implement BlockLot services which includes open, query, subscribe,
and draw in smart contracts. We also develop webbased user interface for using
the lottery services provided by BlockLot. The web interface allows the user to
verify the lottery as well.
