Solana Activates Alpenglow on Devnet and Testnet

Overview

• Anza moved the Alpenglow upgrade to Solana’s public devnet on Sept. 25 after the testnet transition the day before, giving developers and validators a live place to test changes with no real funds at risk.
• Alpenglow’s first phase, called Votor, removes validator vote transactions from blocks and uses direct vote certificates so a block can finalize in one voting round when validators holding at least 80% of stake agree.
• The roughly 150-millisecond finality figure comes from simulations and internal tests and has not been demonstrated under live‑market conditions because mainnet remains on TowerBFT and has no firm Alpenglow activation date.
• Services that build transaction histories, explorers, bridges, exchanges and some validators must update tooling because votes will no longer appear in blocks and candidate blocks may be exposed, while simple wallet apps that only read balances do not require migration.
• Next steps include Agave client releases and a later Rotor phase to handle block distribution, and real-world settlement speed will depend on exchanges, wallets and other off‑chain checks that decide when to mark deposits as final.