Solana Alpenglow Upgrade Enters Testnet to Reduce Finality to 0.15 Seconds

Solana's Alpenglow upgrade has moved to the public testnet, aiming to slash transaction finality time from 13 seconds to 0.15 seconds. The upgrade replaces the TowerBFT consensus mechanism with the Votor voting protocol, which allows validators to exchange votes directly to reach consensus in one or two rounds. Anza has recommended the Agave 4.3 client for validators, with a tentative mainnet launch date of September 28. While Firedancer and Frankendancer do not yet support the upgrade, the phased deployment strategy aims to mitigate risks associated with single-client dependency.