A method includes broadcasting, by a node computer, a propose message comprising a new block for a blockchain to a plurality of node computers in a network shard. The node computer can receive at least one vote message from the plurality of node computers, the at least one vote message indicating verification of the new block. The node computer can, after a predetermined amount of time, receive a plurality of pre-commit messages comprising at least the new block and a block certificate created based on the at least one vote message. If the number of received pre-commit messages of the plurality of pre-commit messages is greater than a quorum value associated with the network shard, the node computer can commit the new block to the blockchain.