The mainnet has been launched by decentralised shared sequencing layer Astria, one of the projects aiming to decentralise blockchain ‘sequencers’. A sequencer is a component of a Layer 2 network that compiles transactions that occur on secondary networks in order to record them on the main Layer 1 blockchain (e.g., Ether), and its setup, Astria says, represents ‘a single, permissionless network that can be shared by multiple rollups, providing settlement (i.e., bridging) and decentralised sequencing with fast (~2 second) block times and a single block time. seconds) block times and single-slot terminality.’