Holešky testnet enters wind down phase as Ethereum moves on

The Ethereum Protocol Coordination team has confirmed that the Holešky testnet, once the network’s largest staging ground for validators, will be shut down two years after its launch. 

The announcement came Tuesday through EF’s official blog page, with developers stating that most remaining validator nodes will be taken offline two weeks after the Fusaka upgrade finalizes on Holešky. 

Holešky, launched in 2023, was created to test validator operations and staking at scale. Over its two-year lifespan, it allowed thousands of validators to make trial upgrades, including the Dencun and Pectra upgrades, both of which introduced improvements to Ethereum’s network efficiency.

However, as covered by Cryptopolitan earlier this year, the developers announced that the network ran into technical bumps after the Pectra activation. The issues contributed to the decision to retire Holešky and move testing operations to newer testnets.

Holešky struggles with problems post-Pectra upgrade

On March 18, Ethereum developer Tim Beiko wrote on the foundation’s blog that the Pectra testnet activation experienced issues with deposit contract configurations on Ether’s testnets. Sepolia recovered smoothly, but Holešky was marred with extensive inactivity leaks that strained its recovery process.

According to Beiko, when the network finalized blocks, a large number of validators were forced into the exit queue. It would take around one year for those validators to be fully removed from the set, which makes Holešky unsuitable for testing the complete validator lifecycle “within a reasonable timeframe.”

The testnet’s inadvertent bottleneck didn’t stop staking operators from making test deposits and consolidations, but they were unable to simulate the full spectrum of validator operations at scale. 

Ether developers concluded that the network no longer served its intended purpose, and its end of life cycle is slated to end on September 30.

“Holešky provided valuable insights into large-scale validator operations and helped stress-test critical protocol upgrades. These learnings have directly informed both Hoodi’s design and broader protocol testing practices. Thank you to everyone who contributed to running, maintaining, and testing on Holešky over the past years,” the Coordination team concluded its message.

Hoodi launched as replacement 

Although Holešky was still viable for every Pectra upgrade feature except validator exits, Ethereum developers introduced a new testnet, Hoodi, to address its shortcomings. 

Hoodi, confirmed to have validator set and support for all Pectra features, went live with the Pectra upgrade at epoch 2048 on March 26, at around 14:37 UTC, per the foundation’s records. It is also expected to handle upcoming protocol upgrades, including the Fusaka fork.

Staking operators and infrastructure providers are now advised to migrate testing activities to Hoodi. Meanwhile, application and tooling developers who previously relied on Holešky are encouraged to use Sepolia, the primary testnet for smart contract and decentralized application testing.

Following the wind-down, Ethereum’s testing environment will consist of three key networks. Sepolia handles application and tooling development for the next 12 months, while Hoodi serves staking providers and validator testing up to 2028. 

A third testnet named Ephemery is available for lightweight validator lifecycle testing, resetting every 28 days to give developers fresh testing conditions. Once Fusaka finalizes Holešky, the testnet will be gradually taken offline. 

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