When the history of blockchain is written, one of its most defining moments will be the years-long process culminating in September, when Ethereum developers pulled off a massive upgrade to its protocol known as “the Merge.”
Switching the core of Ethereum’s blockchain mechanism from proof-of-work (PoW) to proof-of-stake (PoS) without any downtime was no small undertaking. It involved at least two years of testing and over 100 bi-weekly calls to maintain the $30 billion ecosystem that houses non-fungible tokens, crypto exchanges and other decentralized applications. Developers likened the task to swapping out a car’s gas engine for an electric one while speeding down the highway.
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Vitalik Buterin is the co-founder, visionary and spiritual leader of the Ethereum ecosystem. He wrote the original white paper for Ethereum in 2014, in which he laid out the steps the blockchain would tackle in the years ahead, including the Merge.
Buterin had six years of Bitcoin’s existence to observe and improve upon. By transitioning from proof-of-work – Bitcoin’s mechanism that used miners expending enormous computing power, and therefore enormous energy, to add transactions to the digital ledger – to proof-of-stake, which instead uses validators to approve blocks to the blockchain, Ethereum would reduce its carbon footprint by 99.9%. It would also increase the security of the blockchain and allow developers to introduce scalable upgrades to the blockchain in the future.
While the vision and the basic blueprint was Buterin’s, what made the Merge an exceptionally difficult undertaking was that the Ethereum developers prioritized keeping the chain live during the switch.
“There's a much easier way to do the Merge: We shut down for three days, do the thing and flip the switch back on and it restarts,” said Tim Beiko, protocol support lead at the Ethereum Foundation (EF). “We probably would have saved maybe somewhere between a quarter and a third of the work. So getting this switch to happen, basically seamlessly in a way that was like incentive compatible with miners, was pretty wild.”
The Merge could not have been accomplished without dozens of teams of developers, researchers and volunteers, both at Ethereum core and its clients. A client is a software that is used by the nodes operating the blockchain. The EF, a Swiss nonprofit dedicated to the building of Ethereum, coordinated the many client teams (at least nine of them with about 10-20 people per team) that built the testing, tooling and the actual proof-of-stake Beacon Chain into which the proof-of-work version of Ethereum merged. The massive undertaking involved multiple test nets, which are development versions of the blockchain to verify the soundness of the tasks. Many incremental steps had to be taken before the Merge could go ahead.
Amidst all of these contributors, here are a few key developers who took this eight-year-old idea of Buterin’s and willed it to happen, successfully pulling off the massive upgrade that took place on Sept. 15:
Beiko has been the protocol support lead at the EF since January 2021. He often leads the agenda on Ethereum’s All Core Developers Calls, a bi-weekly meetup of the network’s main engineers, and was in charge of coordinating the client teams who work with EF.
When he’s not coordinating and directing traffic for dozens of teams, Beiko decompresses by tending to and hiking with his dog, Dodam, named after a Hong Kong restaurant specializing in Korean fried chicken.
An occasional pastor (he preaches Sunday sermons at a Baptist Church from time to time), Edgington is the lead product owner at Teku, an Ethereum client built by R&D firm ConsenSys. Edgington built out the Teku product team, where he worked closely with the ConsenSys Besu team, Ethereum’s execution client.
Jayanthi has been a devops engineer at EF since December 2020, after discovering on Twitter the EF was seeking to fill the position. An avid fan of fusion music, Jayanthi pioneered the testing of the Beacon Chain and helped coordinate shadow forks, which were crucial tests that helped debug any issues that arose.
Kalinin has a passion for detail and history, as evidenced by his hobby of reconstructing costumes from the 13th, 14th and 16th centuries. He is a lead researcher at ConsenSys who many developers have described as a significant driving force behind the Merge; without him, there might be no Merge. He was instrumental in designing the actual mechanism and wrote the specifications for implementing the Merge.
Marius Van Der Wijden
Even in his free time, Van Der Wijden likes to build. He enjoys Factorio, the crowdfunded video game where he builds massive virtual factories. In his day job as a software developer at EF, during the runup to the Merge Van Der Wijden wrote guides for the Consensus Layer clients so they could use their software with Geth, a client of Ethereum. He also created tools that were used during shadow forks to create bad blocks that would identify issues in some clients.
Wang has been a researcher at EF since 2017, where she worked on sharding, a method that should help address network congestion and high gas fees by spreading transactions across databases, or “shards.” Eventually she was pulled into working on the Merge, and specifically worked on Consensus Layer specifications.
Back in August 2021, Wang famously created a meme to visually express the Merge both in concept and progress over time. A white bear (proof-of-work Ethereum) and a black bear (proof-of-stake Beacon Chain) do the Dragon Ball Z Fusion Dance, moving closer and closer until they morph into a black-and-white panda. The meme went viral and was even turned into NFT, the revenue from which she devoted in part to nonprofit animal welfare organizations.
Zouarhi joined ConsenSys as a research engineer in 2017 and then became a product lead for Besu, an execution client of Ethereum, seeing the Merge build through June when most of the heavy lifting was completed. Her main priorities included working with core developers and laying out what the priorities were for the Besu client team.
A keen fan of “Star Wars” and especially the red-and-black-faced Sith warrior and schemer Darth Maul, whom she enjoys cosplaying, Zouarhi currently is a product manager at Blocknative, where she is working on Maximal Extractable Value (MEV).
With the Merge accomplished, Buterin has shared a roadmap for Ethereum to next address a host of issues including security, privacy, censorship, scalability issues and more, such as sharding.
The Ethereum developers said they hope they have inspired other blockchains, such as Dogecoin, to switch to PoS. PoW chains have come under more scrutiny from regulators due to their environmental impacts. Edgington shared that the European Union “is already talking about turning off PoW, due to the energy crisis.”
“It is fair for them to have waited for Ethereum and be like, ‘this thing works.’ And now that it does, I honestly don't believe that there's a reason” they shouldn’t move over, said Beiko to CoinDesk.
To make that process easier, developers have shared their Merge resources with the rest of the world. “If someone wants to go through the Merge, they can just take that and reuse the testing infrastructure,” said Jayanthi.
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