Table of contents

Deprecate support of Ethereum Classic

Principle of maximum consensus and user choices, why Ethereum Classic now fails the test, and some practical reasons.

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I have been supporting the development of Ethereum Classic since the early days. However, as of today, I have planned to deprecate my support of this particular blockchain.

In this final post of this blog, I want to explain the reasoning. I’ll first explain a core developer guideline which I call principle of maximum consensus and user choices. I’ll then explain why Ethereum Classic now fails the test of that principle due to loss of immutability. In the end, I’ll also discuss some practical reasons that I withdraw my support.

Principle of maximum consensus and user choices

Blockchains, in essence, are about reaching consensus. In a decentralized way, users reach consensus of the current “world state” of a blockchain, in particular, how much money an account has, and what then end result of a smart contract execution is. Without consensus, blockchains do not exist.

The reality is that there are many blockchains. On one hand, varities should be encouraged for competition, and for healthy development of the ecosystem. On the other hand, unnecessary splits should be minimized, because otherwise, there will be no consensus in existence.

Core developers participate, and arguably play an important role in maintaining the ecosystem. Private influcences and even bribery are inevitable. However, it does not mean that core developers have to become puppets. As with many other engineering fields, blockchain developers can also define their own ethics and guidelines to follow, in order to maximize social benefits – make consensus more likely, user choices more respected, and the ecosystem more healthy. Ethics and guidelines allow us to contribute to the broader blockchain community, and not just our own pockets. By keeping the ecosystem’s health and growth, we make blockchains as a whole more valuable, and thus our own work more valuable.

We discussed above that we want to maintain two things – consensus and user choices. On one hand, maintain consensus, to minimize disruptions and splits, because they bring confusion and loss of money to investors. That means, unless there are good reasons, core developers should follow the consensus of the majority. On the other hand, respect user choices. That means, when conflicts happen, it is not ethical for core developers to censor a voice. Rather, we should encourage discussions, provide signaling solutions and support both sides, in order to give time and space for all sides involved to resolve the conflict.

  • Consensus: disruptions and splits should be minimized, because otherwise consensus does not exist.
  • User choices: blockchains are used by users. Varities and healthy competitions should be encouraged.

This issue of consensus and user choices is particularly apparent during a hard fork process, because hard fork is when the majority of disruptions and splits happen. Here we argue about two different point of time during a hard fork, pre-hard-fork and post-hard-fork.

  • Pre-hard-fork: this is the time when the hard fork has not yet happened. Splits and disruptions do not happen at this time. As a result, if conflicts happen, we should prioritize discussions – provide implementations for all sides, and conduct signaling and voting solutions when possible, in hope of the conflict can be resolved during this process.
  • Post-hard-fork: this is the time when the hard fork has happened. Splits and disruptions, if they happen, start to damage the blockchain. As a result, consensus should be prioritized unless there are good reasons. That means, core developers should follow the majority of consensus, unless there are current principle, philosophical, or technical reasons to support other sides.

During pre-hard-fork, if discussions are not encouraged or if any side is censored, it harms healthy competitions and can cause better solutions to be ignored. During post-hard fork, if majority of consensus is not followed unless with good reasons, a blockchain can easily split into many different ones of the same thing, with the essential functionality of the blockchain being lost.

Another important thing to discuss is about good reasons to artifically cause a split. A fundamental difference in principle, philosophy and technical implementation is a good reason. The reason must also be current, meaning that this must be the last possible point when the difference has to appear on-chain. If two parties claim to hold different goals and roadmaps of a blockchain in the future but without any current divergence, then that is not a good reason to cause a split right now. They can continue to stay as one blockchain and split in the future when it indeed becomes necessary.

The principle of maximum consensus and user choices can be summerized as follows:

Core developers should, prior to a hard fork, maximize choices for users, and post a hard fork, minimize possibility of splits.

Failing the test for Ethereum Classic

Ethereum Classic (ETC) is unique among all Etheruem-based blockchains, in that it is one of the only blockchains among them that was created during a split, unlike others which only reuse the codebase with completely new genesis blocks. This is what makes it relevant to discuss the principle of maximum consensus and user choices in regards of Ethereum Classic.

We must first acknowledge that the original reason ETC artifically caused the split was a good reason. When the ETC side argues that theDAO breaks the principle of code-is-law and immutability, it is an apparent philosophical difference that must be respected. However, that good reason is no longer accepted among many ETC core developers any more – in Phoenix hard fork of Ethereum Classic, developers decided to intentionally break several low-value smart contracts that have already been deployed on-chain.

The loss of immutability principle for ETC essentially makes it the same thing as Ethereum (ETH), both taking the pragmatic position of immutability, arguing that it should give ways to developments and experiments, even if that slightly trades off stability. There’s nothing wrong with this approach, and in fact, as ETH core developers have put it, because we’re still in the early days of blockchains, this approach has many advantages. However, for ETC, by being the same thing as ETH, it has essentially lost its distingishing factor. If two things are basically the same without even any principle or philosophical differences, if the original good reason that caused the disruptions and splits of ETH and ETC is not longer valid, then I think for a healthy ecosystem of Ethereum, we should follow the majority consensus of ETH, or support a merge of ETH and ETC.

One argument from some ETC developers is that ETC also has some other distinguishing features on the roadmap. A notable one is that it wants to stay in Proof of Work forever, whereas in Ethereum the goal is to eventually move to Proof of Stake. However, we note that this is not a good reason to cause a split right now, because the split does not have to be immediate. Ethereum is still in solid Proof of Work state, so if only for this reason, both blockchains could still have stayed together until the final days when the move of Ethereum to Proof of Stake happens. The disruptions and splits caused right now are unnecessary.

Practical reasons

There are also practical concerns regarding supporting ETC.

Ethereum historically has a unique property – it has multiple client implementations with competitive shares. It’s not the only blockchain with multiple implementations. Bitcoin has multiple clients as well. However, Bitcoin Core has always dominated the market.

Ethereum’s model requires a collabrative culture among developers. Péter Szilágyi, the lead developer of Go Ethereum, has described the culture quite nicely in various core dev meetings. It basically requires all development teams to hold some basic restraints when dealing with other teams. This avoids “implementation wars”, where implementations spend unnecessary marketing resources to downplay other teams. The restraints are held because all teams recognize that promoting one’s own unique features and performance advantages is beneficial to the team and the ecosystem, while downplaying other teams only incites anger, hurts relationship with other teams, and damages the ecosystem. This basic understanding allows the whole development community to remain competitive, while at the same time, be able to work together.

ETC inherited Ethereum’s multiple implementation development model. However, it failed to inherit this essential collabrative culture. Over the past years, we have seen people like Afri Schoedon holding public aggresions towards other clients, teams like ETC Labs actively asking users to switch away from OpenEthereum, copying the MultiGeth codebase to CoreGeth but at the same time removing the credits, and the famous blame game for the later-rejected Aztlan hard fork. The aggressive marketings from various parties have broken the competitive collabration culture of Ethereum Classic, and since made the multiple implementation ideal much harder to realize.

The lack of collabrative culture of ETC has made bugs and issues much harder to handle. When provocations and not-my-problem attitudes become the norm, we can hardly focus on the bug but spend the resources on blaming others. This has made supporting ETC a huge liability – teams do not want to congrats each other because they want to promote their own implementations, but whenever things go wrong, teams will not hesistate to blame others.


With ETC dropping its principle of immutability, following the principle of maximum consensus and user choices, it has become a non-majority blockchain that was in almost all aspects same as Ethereum, including philosophy and principles. Supporting it will mean supporting unnecessary disruptions and splits, with no good reasons right now. The future of Ethereum Classic might follow a different roadmap than Ethereum, but that is not a good reason to have already split now.

I wrote the first ETC-specific EVM implementation SputnikVM, maintain MultiGeth and ETC support for OpenEthereum. Involved in Ethereum Classic for so long, I wish the ETC community well with good faith. However, in its current form, it has become a blockchain that I cannot provide development support to.


What about other Ethereum-based blockchains? Do you continue to support them?

Yes. I’ll continue to support all other Ethereum-based blockchains. Unlike ETC, other Ethereum-based blockchains do not undermine the principle of maximum consensus and user choices. ETC is the only Ethereum-based blockchain I know that was created in a split of Ethereum mainnet. Other Ethereum-based blockchains only use the Ethereum codebase, but with completely different genesis blocks, and thus do not qualify as splits, and do not cause disruptions.