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Finalized no. 29

the Ethereum consensus-layer

Posted by Danny Ryan on September 28, 2021

Finalized no. 29

Altair is here; the Merge is coming.


  • Altair upgrade epoch set, mainnet client releases in progress πŸ‘€
  • Merge interop spec released. Devnets to follow 🏺

Altair upgrade, Oct 27

Altair, the first mainnet upgrade to the Beacon Chain, has been scheduled for epoch 74240 (Oct 27, 2021, 10:56:23am UTC).

A subtle but great advantage of proof-of-stake is that we can precisely time upgrades (Sorry Tim! We'll be done with proof-of-work soon πŸ˜‰)

This upgrade brings light-client support to the core consensus, cleans up beacon state incentive accounting, fixes some issues with validator incentives, and steps up the punitive params as per EIP-2982.

Huge shout-out to client teams for their work on this throughout the year πŸ™Œ

Keep your eyes peeled for another blogpost on Monday, October 4th. This will include all mainnet Altair releases.

And then you can upgrade your nodes!

Merge interop specs and coming devnets

The Merge Interop spec was released on Friday. This "meta-spec" provides stable targets for engineers for an initial wave of testing and devnets.

After a flurry of specification activity over the past few months, Merge specs are near feature complete, and the core logic is stable. In this next phase, engineers will build out the Merge logic and test their software with other teams on short-lived devnets. The engineers will vet the specs as they stand today and provide dynamic feedback into the specs to refine and/or fix issues as they arise.

At the top of the list is to validate and refine the Merge engine API and to prototype and specify various versions of sync under the Merge paradigm.

Proof-of-stake superceding proof-of-work is years in the making, and we're just as excited as you to see it in action. Much fun coming in October πŸΊπŸš€

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