Espresso Foundation announced that the Espresso mainnet upgrade has been completed. Around 100 validators coordinated the implementation on September 9, reducing transaction final confirmation time to under 1 second. This upgrade has restructured the consensus, network, block construction, and data availability architecture, cutting the required network hops for final confirmation from over 7 to just 3, and eliminating the dependency of block finality on the survival status of subsequent leaders. The validator network has transitioned from CDN relays and libp2p gossip to a Cliquenet encrypted full-connection network, enabling single-hop transmission of consensus messages. Block construction has also been migrated from external services to leader nodes. The upgrade introduces a new erasure coding scheme, an optimized Reed-Solomon library, and BLAKE3, while parallelizing the encoding, verification, and recovery processes. Espresso stated that the workload for block construction, data availability, and voting required for each final confirmation block has been reduced by about two-thirds, along with lower hardware and bandwidth requirements for validator nodes. https://(wublock123.com)/news/espresso-mainnet-upgrade-final-confirmation-under-1s-network-architecture-rewrite-68385