Solana's Alpenglow consensus upgrade is active on devnet and testnet, creating a testing environment for application teams, validators and infrastructure providers before any mainnet deployment. The Votor consensus system replaces TowerBFT and targets transaction finality of about 100 milliseconds when at least 80% of stake responds, or about 150 milliseconds in fallback mode, compared with roughly 12.8 seconds under the existing system. Votor moves validator coordination off-chain and aggregates votes into BLS certificates, reducing block space used by technical vote transactions while leaving the Solana Virtual Machine, smart-contract structure, transaction formats and fee mechanics unchanged. Anza activated Alpenswitch on devnet at epoch 1167 after a 5,000-slot, roughly 17-minute countdown, one day after the testnet transition. Solana co-founder Anatoly Yakovenko highlighted the release in a brief comment, while Anza continues stability monitoring and has not disclosed a mainnet-beta integration timeline.