Ethereum Launches First Mainnet Shadow Fork in Preparation for Merge

As Ethereum approaches its long-awaited transition to proof of stake, developers have launched the mainnet’s first “shadow fork”. Its purpose is to stress-test existing assumptions about testnests and the mainnet.

Preparing for the Merge

According to Ethereum Foundation Developer Parithosh Jayanthi, the fork adds merge related fields to the configs of existing testnets. “In doing so, we essentially inherit the state/txs of the canonical testnet,” he tweeted on Friday.

Through inheriting the state of existing testnets, the developer’s assumptions around syncing and block construction time may be stress tested. The shadow fork stays connected to peers on the canonical Ethereum chain, meaning some transactions will appear on both chains.

For context, Ethereum has been planning to transition its network from a proof of work to a proof of stake consensus model for years. Proof of work requires energy to be spent in order to construct a block, whereas proof of stake requires cryptocurrency to be staked. The transition will significantly reduce Ethereum’s energy requirement, which many have come to oppose about Bitcoin.

The upgrade has been nicknamed “the merge” as it will involve merging the Ethereum mainnet with the beacon chain. The beacon chain will serve as the spine of Ethereum 2.0, constantly scanning and validating transaction data.

According to the new shadow fork’s block explorer, Over 2,231,000 transactions have already been processed. It also has over 1 million wallet addresses registered and over 14.5 million blocks, each with a production time of 13.1 seconds.

Van Der Wijden, another Ethereum Foundation dev, called today’s shadow fork a “historical event”. Meanwhile, developer Tim Beiko states that the success of this fork is key to determining the date of the actual merge. Ethereum founder Vitalik Buterin claims that the Merge should occur before July of this year, but dates for the upgrade have been pushed forwards multiple times before.

Is it Working?

Jayanthi claims that some issues have been noticed with Nevermind and Bisu – Ethereum-based software providers – following the fork. However, they are reportedly minor in severity.

Multiple other testing events for the Ethereum merge have already played out successfully. For example, the Klin testnet merge went off well in mid-march, which merged a proof of work execution layer with the Beacon chain. Klin is the final testnet for Ethereum 2.0 before the actual merge.