Solana Prepares Alpenglow Testnet Rollout, Targets 150-Millisecond Finality

Solana Prepares Alpenglow Testnet Rollout, Targets 150-Millisecond Finality

September 23, 2026
3 min read

Key Takeaways

  • Solana’s Alpenglow update is being prepared for deployment on its public test network, where developers are targeting finality of roughly 150 milliseconds, down from 12.8 seconds.
  • The initial testnet migration requires Agave 4.3; Firedancer and Frankendancer are not yet supported.
  • September 28 is a tentative software feature activation date, not a confirmed Alpenglow launch.

Solana is preparing its Alpenglow upgrade for public testnet deployment, where developers will try to reduce transaction finality time from about 12.8 seconds to 150 milliseconds.

The rollout expands testing beyond a dedicated community network, where Alpenglow has operated for more than four months. However, Anza’s tracker still showed the testnet switch as pending on September 23, CoinDesk reported.

How Alpenglow Could Speed Up Solana Finality

Alpenglow is now being introduced on Solana’s public test network. The public testnet is a separate network where developers can test upgrades without risking mainnet funds. This lets developers test the migration, find issues, and restart the network without risking users’ money.

Finality marks the point when a transaction becomes part of the blockchain’s permanent record. Exchanges, bridges, and merchants all require confirmed transaction finality before releasing funds or completing payments.

Faster finality could shorten settlement waits for exchanges, cross-chain bridges, and merchants. Solana’s documentation identifies near-instant checkout confirmation as one potential benefit.

Solana currently uses the TowerBFT system to record validator votes as transactions and accumulates them across 32 slots before finalizing a block. Alpenglow replaces that system with a voting protocol called Votor. It lets validators exchange votes directly and reach finality in one or two voting rounds.

Alpenglow has spent over four months running on a smaller network created specifically for the upgrade. The migration will test whether validators and supporting services can upgrade together.

According to Solana’s documentation, Votor can finalize a block in one round with votes representing at least 80% of stake, or in two rounds using a 60% stake threshold.

The original 150-millisecond median estimate came from simulations that excluded computation overhead. The estimate is not a guaranteed finality time for every transaction.

What Alpenglow Changes for Users and Validators

Signing and sending transactions would remain unchanged for users. Alpenglow preserves Solana’s transaction execution system and fee mechanics, although infrastructure providers must adapt how they process block data.

The 150-millisecond finality target is separate from efforts to shorten block-production slots.

Participating testnet validators need Agave 4.3. Jump Crypto’s two alternative validator clients, Firedancer and Frankendancer, do not yet support the Alpenglow test.

These alternatives aim to reduce Solana’s reliance on a single piece of software. Independent validator clients can reduce the risk of a single software flaw disrupting the network.

Anza’s tentative schedule lists September 28 for resuming Agave 4.3 feature activation on mainnet.

However, it is not a confirmed Alpenglow launch date, and Anza’s tracker still showed the testnet switch as pending as of early Wednesday.

Get started on WEEX with a simple 40 USDT reward. Deposit 100 USDT, make your trade, and claim the bonus. 

Disclaimer: All content on The Moon Show is for informational and educational purposes only. The opinions expressed do not constitute financial advice or recommendations to buy, sell, or trade cryptocurrencies. Trading involves significant risk and may result in substantial losses. Always seek independent financial advice before making investment decisions. The Moon Show is not responsible for any financial losses or decisions made based on the information provided.

Please view the full disclaimer at: https://themoonshow.com/disclaimer



Previous Article

ECB, EU Central Banks Urge Removal of Stablecoin Bank Deposit

The European Central Bank (ECB) and EU national central banks called for removing mandatory ban...

Next Article

XRP Ledger Revives Upgrade to Separate Payment and Compliance Roles

XRP Ledger developers introduced an upgrade that could soon let banks and token issuers assign ...