paris.md

Paris Upgrade Specification

The Paris specification corresponds to the execution layers changes associated with Ethereum's transition to proof-of-stake, a.k.a. The Merge.

Included EIPs

Specifies changes included in the network upgrade.

• EIP-3675: Upgrade consensus to Proof-of-Stake
• EIP-4399: Supplant DIFFICULTY opcode with PREVRANDAO

In addition to the EIPs listed above, an EIP-2124 FORK_NEXT value must be set for the Paris upgrade to allow nodes to disconnect stale peers. In typical upgrades, this happens on the fork block. Because Paris uses a Terminal Total Difficulty instead of a block number to trigger the proof-of-work to proof-of-stake transition, this value must be set after the transition has completed. See the FORK NEXT Upgrade section for more details.

Engine API

A new set of APIs is introduced as part of The Merge for the execution layer clients to communicate with the consensus layer. The specification for it is available here.

Consensus Layer Specifications

This network upgrade requires changes to both Ethereum's execution and consensus layers. The consensus layer specifications for this upgrade are available here.

Upgrade Schedule

Proof-of-Work to Proof-of-Stake Transition

Network	Terminal Total Difficulty	Expected Date	Fork Hash
Ropsten	50000000000000000	June 8, 2022	0x7119B6B3 (unchanged from London)
Sepolia	17000000000000000	July 6, 2022	0xfe3366e7 (unchanged from Genesis)
Goerli	10790000	August 10, 2022	0xB8C6299D (unchanged from London)
Mainnet	58750000000000000000000	September 15, 2022	0xf0afd0e3 (unchanged from Gray Glacier)

FORK NEXT Upgrade

Once the proof-of-work to proof-of-stake transition has completed, an additional upgrade is required to add an EIP-2124 FORK_NEXT value to clients on the network in order to disconnect stale peers.

Network	Block Number / FORK_NEXT	Expected Date	Fork Hash
Ropsten (deprecated)	N/A	N/A	N/A
Sepolia	1735371	August 17, 2022	0xb96cbd13
Goerli	TBD	TBD	TBD
Mainnet	TBD	TBD	TBD

Note that Ropsten has been deprecated and will not be upgraded with a FORK_NEXT value.

Client Releases

• Ropsten:
  • Besu
  • Erigon
  • go-ethereum (geth)
  • Nethermind
• Sepolia
  • Besu
  • Erigon
  • go-ethereum (geth)
  • Nethermind
• Goerli
  • Besu
  • Erigon
  • go-ethereum (geth)
  • Nethermind
• Mainnet
  • Besu
  • Erigon
  • go-ethereum (geth)
  • Nethermind

Readiness Checklist

See https://github.com/ethereum/pm/blob/master/Merge/mainnet-readiness.md

Client Integration Testnets

• Amphora
• Pithos
  • Quickstart
  • Configs
  • Explorer
• Kintsugi
  • devnet-0
  • devnet-1
  • devnet-2
  • devnet-3
  • devnet-4
  • devnet-5
• Kiln
• Goerli Shadow Fork 1
• Goerli Shadow Fork 2
• Goerli Shadow Fork 3
• Goerli Shadow Fork 4
• Goerli Shadow Fork 5
• Goerli Shadow Fork 6
• Mainnet Shadow Fork 1
• Mainnet Shadow Fork 2
• Mainnet Shadow Fork 3
• Mainnet Shadow Fork 4
• Mainnet Shadow Fork 5
• Mainnet Shadow Fork 6
• Mainnet Shadow Fork 7
• Mainnet Shadow Fork 8
• Mainnet Shadow Fork 9
• Mainnet Shadow Fork 10
• Mainnet Shadow Fork 11
• Mainnet Shadow Fork 12
• Mainnet Shadow Fork 13