Solana's biggest planned speed upgrade has passed another milestone. Alpenglow, a rebuild of how the network confirms transactions, is now running on both of Solana's public test networks, according to CoinDesk.
The goal is ambitious: cut the time it takes for a transaction to become final from about 12.8 seconds to roughly 150 milliseconds, faster than the blink of an eye.
Where things stand
Anza, the company that builds Solana's core software, said Alpenglow went live on Solana's developer network (devnet) on September 25, a day after the separate testnet finished its own switch-over.
The two networks serve different jobs:
Reaching both is an important step, because it means the upgrade is being exercised by real developers and real validator setups, not just in lab conditions.
What hasn't happened yet is the big one: there is no date for Alpenglow on Solana's main network. And the 150-millisecond target hasn't yet been proven under the pressure of live markets with real money moving.
What Alpenglow actually changes
Today, Solana uses a consensus system called TowerBFT, which is how validators agree on the order and validity of transactions. Alpenglow replaces it with a new system called Votor.
With Votor, validators can finalise a block after one or two rounds of direct voting. That's a big part of how the upgrade gets from seconds to milliseconds.
Importantly, it doesn't change how ordinary users send tokens. The change is under the bonnet, in how the network reaches agreement.
A side effect worth knowing
There's one change that could confuse people watching the charts. Alpenglow removes validator votes from blocks. Today, those votes are counted as transactions, which inflates Solana's reported transaction numbers.
Once Alpenglow is live, Solana's headline transaction count is likely to drop, even if real user activity stays exactly the same. Anyone comparing network activity before and after the upgrade will need to keep that in mind.
Why finality matters
"Finality" is the point at which a transaction can't be reversed. For most people, a few seconds doesn't sound like much. But for trading, payments and anything automated, faster finality matters a lot:
It also puts Solana in a strong position in the ongoing race between blockchains to offer the fastest, cheapest settlement.
The bottom line
Alpenglow reaching both public test networks is real progress for one of Solana's most important upgrades. The promise of 150-millisecond finality is exciting, but the hardest test is still ahead: running it on mainnet, with real money and real traffic. Until a launch date is set, it's a milestone rather than a finish line.
This article is for information only and is not financial advice.
Sources: CoinDesk and Anza announcements, September 2026.