EVM Smart Contract Blockchain Overview Part 01: Proof of Work

Here Neuron starts a three part series to explore different EVM Smart Contract Blockchains and provide a complete overview: ETH, ETC, RSK, CLO, POA, xDAI, VET, GO, TOMO, and TRON.

EVM Smart Contract Blockchain Overview Part 01: Proof of Work

Recently a smart contract development company published a story where they announced that they are abandoning development on EOS and will focus on ETH platform exclusively. A big reason for that was their realization that tooling matters. Ethereum is the clear winner in smart contract platform battle not because of the users - let's be honest, users care about what the product does for them, not what blockchain is being used - but because of winning the developer mindshare. Platforms like EOS and Tezos, having raised billions of dollars in their ICOs, failed to invest this money in smart contract dev kits and thus struggle to attract devs who will make their blockchains useful.

However, the beauty of open source allows one to customize Ethereum and build other blockchains that can leverage the hundreds of millions of dollars invested in Ethereum tooling. This compatibility magic hides behind three letters - EVM, which stands for Ethereum Virtual Machine. It means that the code that developers write gets compiled into EVM bytecode and is then the blockchain runs EVM and executes these smart contracts. You could say that today EVM is the leading industry standard.

We are happy that we foresaw this back in 2017 when we announced that we plan to release all our products - our decentralized exchange, our dApp wallet, and our upcoming Ethereum Dapp Kit - on all EVM compatible blockchains. Currently our project is actively fundraising to bring this plan to life.

Which begs the question: what are those EVM compatible blockchains and which ones would be best suited for our products? Let's have a look at some of the top contenders and discuss their security models, transaction speed and how they differ from each other.

EVM Smart Contract Blockchain Overview

Our EVM Smart Contract blockchain overview is broken down into three parts covering different types of consensus algorithms, Part II and Part III will be published over the next few days.

  1. Proof of Work (Part I)
    1.1 Ethereum (ETH)
    1.2 Ethereum Classic (ETC)
    1.3 RSK
    1.4 Callisto (CLO)
  2. Proof of Authority (Part II)
    2.1 POA Network (POA)
    2.2 xDAI
    2.3 VeChain (VET)
  3. Other Consensus Algorithms (Part III)
    3.1 Cardano (ADA)
    3.2 GoChain (GO)
    3.3 TomoChain (TOMO)
    3.4 TRON (TRX)
    3.5 ThunderCore (TT)
    3.6 Loom Network (LOOM)
    3.7 Volume Network (VOL)

Ethereum $ETH

  • Ticker: ETH
  • Consensus: Proof of Work
  • Block time: 15 sec

The pioneer. The OG smart contract chain. The smart contract daddy. There are many ways to describe the Ethereum platform, good and bad. One thing is certain though - Ethereum has already made a huge impact on the course of human history and it is only getting bigger now.

Despite some of the ideological differences early on (such as famous theDAO hard fork), and the narrative that Ethereum is centralized around Vitalik, Infura and Consensys which may or may not be true, Ethereum offers high security of financial transactions at high speed and low fees, and allows developers to create dapps and their own digital assets, further adding to the chain's usefulness.

Ethereum's leadership quickly realized that the smart contract chain is only as useful as the dapps that it hosts and thus have invested heavily into its development tools. Perhaps the single most important dev tools project is the Truffle Suite - which by the way recently got a huge grant to port their tools to Tezos, so watch this space!

Ethereum Classic $ETC

  • Ticker: ETC
  • Consensus: Proof of Work
  • Block time: 15 sec

The chain that survived against all odds. Those who have followed the history of crypto know that Ethereum Classic is the original Ethereum chain, continuation of the original idea of an individual having sovereignty over their assets. When the DAO incident occurred in 2016 the Ethereum Foundation had a lot of vested interests in changing the course of history and bailing themselves out. To this date, the code of Ethereum (ETH) chain contains the shameful list of accounts whose rights were violated by what essentially amounts to a political play.

Despite the Ethereum Foundation's best efforts to destroy the chain whose supporters refused to participate in violation of EVM rules the chain survived and is now ushering into a renaissance. We are proud to have contributed greatly to this cause, having developed the first dapp wallet, the first dapp and having created ETC token economy that in less than a year has gone from $0 total market cap to over one million dollars.

Recent price rally of ETC can largely be attributed to the fact that Atlantis hard fork is coming up soon, which will enable more EVM features and give dapp developers more tools to work with and develop better products. The more dapps, the more products the chain has, the more active users it can attract, the higher demand for its base currency and thus the higher the price. The best thing you can do to help your chain grow is to invest in developers.


  • Ticker: none, pegged to BTC
  • Consensus: Proof of Work, merge mined with Bitcoin (18% hashrate)
  • Block time: 33 seconds

RSK was the big hope of 2017 and one of the largest disappointments in the blockchain industry. The sales pitch was fantastic - Write Smart Contracts for Bitcoin. Which developer wouldn't want to write dapps for the most secure blockchain with the largest amount of users and the best brand? We were very excited about its launch, and so were the bitcoin-like chains, e.g. Litecoin (LTC) and Verge (XVG), who wanted to launch smart contracts as well. Even some Ethereum tokens, such as Civic, planned to move from ETH to RSK chain as soon as it was launched.

However, having received $7.3 million USD in funding from a Venture Capital firm, the Argentina based RSK Labs failed to develop their software in time, failed to convince Bitcoin miners to run their merge-mining software, and failed to provide a trustless way to convert BTC from mainnet Bitcoin blockchain to RSK sidechain and back. The only way to obtain their RBTC was to use RSK Labs owned bridge service for which you had to pass KYC. Thank you very much, nobody needs KYC bitcoin.

Right now RSK Labs is simply slowly burning through the $7.3M that they have raised pretending that there are users on their chain and that somebody needs it. At this moment we strongly advise against developing on this chain.

Callisto $CLO

Callisto PoW EVM Smart Contract Overview
  • Ticker: CLO
  • Consensus: Proof of Work
  • Block time: 15 seconds

Callisto is a project that was originated by a team that was working on Ethereum Classic back in 2017 and decided to split away in 2018. Team Saturn was one of the first to cover creation of Callisto Project. The chain is code compatible with ETC at the moment of the fork with an additional feature of cold staking - you can lock your CLO if you don't plan to sell it immediately and receive more CLO funded by miners. Unlike BTC, ETH, ETC, where the miners get full reward for performing proof of work, CLO has taken more of a ZEC approach of taking a portion of mining reward (10% in case of ZCash and a whopping 30% in case of Callisto) and using it to fund the dev team and the cold staking.

Essentially, the dev team receives passive income for as long as someone is mining the chain and regularly dumps these coins on the market (look at the price charts on CoinMarketCap for ZEC and CLO confirms that). In Callisto's defense, they do indeed manage to provide some free smart contract audit services to developers but they are yet to establish a brand whereby their audit would convey any trust in its outcome.

While criticism of such funding approach is valid, and it does create a sell pressure on the blockchain native token CLO, it also allows the core dev team to have sustained funding so they can focus on dev and promotion work and not worry about fundraising, and aligns incentives - the dev team's income is proportional to CLO price. Furthermore, thanks to Cold Staking mechanism long term CLO holders can benefit from the 30% mining subsidy.

Another problem that we foresee with Callisto is that since it is a hash minority chain it is very vulnerable to 51% attacks. Even much larger Ethereum Classic network has once been the victim of such attack which has caused exchanges to increase confirmation numbers to thousands in order to protect themselves. If CLO's price ever goes up to significant levels, exchanges that trade it will have to increase CLO confirmation numbers to perhaps tens or hundreds of thousands of confirmations in order to obtain same security guarantees, which would lead to e.g. CLO deposits taking days!

Thanks to Callisto's active community, and especially twitter user spigfish, we found out that there is ongoing work in the form of PIRLGUARD, which does make it much harder and costlier to execute a 51% attack. At the moment given substantial hashrate (too small compared to ETC and especially ETH, but much larger than most of mineable currencies) and activated PirlGuard 51% attacks on Callisto would likely be unprofitable and thus the chain is reasonably protected. If you still think it is risky it is worth remembering that in a truly decentralized cryptocurrency it is impossible to remove this threat completely (unlike centralized coins like such as Binance Chain or Facebook Libra).

Hope you have liked our overview on EVM Smart Contract Blockchains so far and you are eager to learn more about other EVM chains!

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