Solana’s Alpenglow upgrade activates on developer network ahead of mainnet launch

Solana’s push to make transactions final in a fraction of a second has cleared its second public test network, putting the long-promised Alpenglow upgrade one step closer to real money. Developers building exchanges and payment apps now have a live environment to test against before any changes reach Solana’s mainnet, where actual funds move.

• Alpenglow is now active on both Solana’s devnet and its separate testnet as of this week.
• The upgrade targets roughly 150 milliseconds for transaction finality, down from about 12.8 seconds today.
• Anza has not scheduled a mainnet launch, and the 150ms target remains untested under live-market conditions.

• 150ms target finality time under Alpenglow versus today’s network
• 12.8s current time Solana takes to finalize a transaction
• Sept 25 date Anza announced Alpenglow’s activation on devnet
• Sept 28 tentative date Anza’s schedule resumes feature activations

Solana’s Alpenglow upgrade has reached its public developer network, according to reporting by CoinDesk. The upgrade targets around 150 milliseconds for finality, the point at which a transaction can no longer be reversed, compared with roughly 12.8 seconds under Solana’s existing system. A finality window that short could shorten the wait for an exchange to release a deposit or for a payment app to confirm a sale to a merchant.

Anza flips the switch on devnet a day after testnet transition

Anza, the company that builds Solana’s core validator software, announced the developer-network activation on Friday, September 25, in a post on X. That came one day after the separate testnet completed its own transition to Alpenglow.

The Solana Foundation’s upgrade dashboard now lists Alpenglow as active on both networks. Devnet is where application teams check software using tokens that carry no real value, while the testnet is used mainly to stress-test validator operations under simulated load. Neither network handles funds with market value, which is why the mainnet rollout, still unscheduled, is the step that matters for exchanges and payment processors.

Vote removal will shrink transaction counts without any drop in usage

Alpenglow rewrites how validators, the computers that check and record transactions, reach agreement on the blockchain’s history. Instead of recording their votes as transactions embedded inside blocks, validators will exchange those votes directly, cutting the process to one or two rounds rather than the current multi-step confirmation chain.

That change carries a side effect that will show up in public dashboards before it shows up in wallets. Transaction totals that previously included validator votes will fall even if the number of user payments and trades stays flat, and the Solana Foundation has told data providers to adjust how they compare activity across periods.

Services that build transaction histories will also need to keep competing candidate blocks separate until the network settles on one, since mixing their contents could produce an inaccurate record. The Foundation’s guide states that applications which simply send transactions and read account balances require no changes at all.

No mainnet date yet, and the 150ms figure remains a simulation

Solana has not set a firm launch date for Alpenglow on the network that carries real funds. Anza’s software schedule tentatively allows feature activations to resume on Monday, September 28, but that date is not identified as an Alpenglow launch window.

The 150-millisecond figure itself is still a target drawn from simulations rather than a result demonstrated under live-market trading conditions. Wallet processing time and exchanges’ own deposit checks will add further delay on top of whatever finality Alpenglow ultimately delivers.

The BlockWest read. For exchanges and market makers, the real test is not the 150ms simulation but whether Alpenglow holds up when order flow spikes and validators disagree on competing blocks in real time. Data providers and analytics platforms face a quieter but immediate task: recalibrating on-chain volume comparisons before the vote-removal effect gets mistaken for a drop in actual Solana usage.

Whether Alpenglow’s 150-millisecond target survives contact with live order flow will only be answered once Anza sets a mainnet date, something it has not yet done even as the September 28 activation window approaches.

BlockWest is a news publication. Nothing here is investment advice. Read our disclaimer and editorial policy.