Solana has moved its Alpenglow upgrade to a public test network, with developers working to reduce transaction finality from about 13 seconds to 0.15 seconds.
The proposed change would bring finality down from 12.8 seconds to 150 milliseconds, allowing exchanges, bridges and merchants to treat payments as irreversible almost immediately.
Alpenglow would replace Solana’s existing TowerBFT consensus system with Votor. Under the new system, validators would be able to finalise blocks after one or two rounds of direct voting.
The upgrade is designed to change how the network reaches agreement on transactions, rather than how users send funds. Users would continue to transfer money through Solana in the same way, while the network’s confirmation process would be altered behind the scenes.
The public testnet deployment is the first stage in assessing whether the proposed system can deliver the targeted reduction in finality time. The initial migration requires Agave 4.3, Solana’s validator software, to be installed.
However, the first testnet phase will not support Firedancer or Frankendancer. Both are alternative validator clients, meaning the initial Alpenglow testing will not include those implementations.
A potential Solana mainnet update is currently scheduled for 28 September, but that date remains tentative. It is not a confirmed launch date for Alpenglow.
The distinction between the planned mainnet update and the upgrade itself is important: the date refers to a possible network update, while the Alpenglow launch still depends on the outcome of testing.
