Sequencers are are chosen to propose blocks via random election from the validator set.

When chosen, the sequencer collects transactions from the network, builds blocks, and sends them to the sequencer network for validation.

Sequencers who are not currently producing blocks play the important role of providing signatures attesting to the validity of upcoming blocks.
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Once enough signatures are obtained, blocks are included on Mainnet and zk proofs of these blocks are sent to Ethereum for settlement.

The Aztec Network is governed by sequencers, who coordinate to propose and vote on governance proposals.

If a proposal passes, sequencers are responsible for implementing the upgrade by pointing to the newly proposed contracts.