The network of Ethereum layer-2 rollups using zkSync’s ZK Stack got a new addition on Thursday with the launch of the Cronos zkEVM testnet.
Blockchain developer Cronos Labs is developing its third blockchain, the first to use ZK Stack hyperchain to achieve a live testnet.
The first chain in the Cronos ecosystem was a Cosmos app chain, developed in partnership with the Crypto.com exchange and launched in 2021. Cronos then followed up with an EVM-compatible chain, also built using the Cosmos SDK in 2022 This new effort augments, but does not replace, the previous two chains.
Cronos’ zkEVM is the result of a collaborative effort between Cronos Labs, Matter Labs (the team behind zkSync), and several technical teams from Crypto.com stakeholders and dapp developers on the existing chains.
The zkEVM testnet is built on top of the Ethereum Sepolia testnet and uses zkSync’s new open source prover, Boojum, a STARK-based zero-knowledge proof system, which stands out for its low hardware requirements and low cost in the layer 2 rollup space.
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Launching a native Ethereum chain was motivated by frustrations with bridging EVM chains and between Cosmos and Ethereum, said Ken Timsit, general manager at Cronos.
“Of course, when we started building Cronos as an EVM chain, we were already convinced that the Ethereum developer ecosystem has a richness and robustness that cannot be compared when it comes to building DeFi and NFT applications,” Timsit told Blockworks.
Good relationships with Matter Labs and the desire to contribute to the open source development of the ZK Stack led them to take the next step.
Hyperchains share components of the ZK Stack, including a shared native bridge to the Ethereum mainnet and zkSync’s reliable bridging mechanism, where assets remain secured by Ethereum.
It will also benefit from zkSync’s proprietary account abstraction, allowing payment of transaction fees in various cryptocurrencies, such as the Cronos token (CRO).
“If you look at legacy chains, it is very difficult to migrate Ethereum assets, for example to wallets that allow account abstraction,” Timsit said. “And so for us, starting with account abstraction by default is a way to take advantage of what this technology offers, better than what we can do on a chain that already has an ecosystem of wallets and tokens.”
Cronos’ zkEVM is expected to transition to mainnet in the second quarter of 2024.
Growing hyper chains
A handful of other hyperchains are in development using the ZK Stack, most notably GRVT (pronounced “gravity”), a derivatives exchange, and Tradable, which is working to bring private credit to the chain.
Tradable plans to have an institutionally focused hyperchain, which will eventually form a decentralized chain with other institutional partners, said Omar Azhar, head of business development at Matter Labs.
“I think you could see app-specific chains and then ecosystem-specific chains,” Azhar told Blockworks.
Matter Labs sees the zkSync hyperchain as strictly a better option than app-specific chains in Cosmos, like Cronos’ previous efforts, said Marco Cora, senior vice president of business and operations. That’s because Cosmos chains generally need to provide their own validator set and security, and don’t have native token bridges to Ethereum.
“If you’re an appcha developer, why are you taking on these two extra projects that you shouldn’t really be focusing on: building the bridge and starting up the security?” Cora told Blockworks.
The ZK Stack competes with other well-funded networks building zkEVM chains, including Polygon, whose Chain Development Kit (CDK) shares many of the same goals, and StarkWare’s Starknet, the precursor to STARK prover technology that both Polygon and zkSync have built on. repeated.
Hyperchains can also serve the purpose of private blockchain frameworks such as Hyperledger or Corda, Cora said, but with all the benefits of Ethereum.
“They are technically very scalable, but they are not practically scalable. “If you talk to most companies, they say this is way too expensive for what it is for me,” he said.
In addition to cost considerations, there is the problem of social coordination.
“If you’re Goldman Sachs, you don’t want to join the Morgan Stanley Chain just because it’s the Morgan Stanley Chain. If you’re Fidelity, you don’t want to join the BlackRock Chain just because it’s the BlackRock Chain and so on,” Cora said.
“But if the chain sponsor were to force themselves to create a ‘zero-knowledge proof’ and hand this proof over to a third party – namely Ethereum – they could now claim a much higher degree of credible neutrality,” he added . “Now this party cannot tamper with the system.”
