ZK (Zero Knowledge) rollups have become one of the main scaling narratives in blockchain. As of July 2024, there are multiple ZK Rollup projects implementing different techniques to scale Ethereum. Developments focused on Bitcoin started gaining traction, too. In this article, we'll take a look at 5 promising ZK projects using rollup technology.
5 Promising ZK Rollup Projects as of July 2024
Rollups are Layer 2 solutions to help public blockchains solve one of their main technological challenges: achieve scalability without compromising security or decentralization. Operating on top of main networks, they process complex computations separately from the mainnet, thus enabling a higher number of transactions in less time. There are two main types of rollups: Optimistic and Zero Knowledge, named based on the cryptographic method they use to validate transactions.
ZK rollups are based on the Zero Knowledge technology, which proves the correctness of a statement without revealing the statement itself. This way, batched transactions get verified faster, which in turn, reduces fees associated with highly congested networks.
There are multiple ZK rollups focused on different aspects of a blockchain, such as transaction speed, cost-efficiency, and compatibility. Below, we list 5 of the most promising ZK rollups.
For a more detailed explanation of ZK rollups, check out our “ZK-rollup: The Next Level in Blockchain Scaling,” article.
1.Taiko
Taiko scaling solution. Source: Taiko.xyz
Taiko is a based Ethereum rollup that relies on Ethereum's existing processes for transaction sequencing. On Taiko, transactions are posted to Ethereum first, defining the block order, and then they are proven off-chain. The solution batches multiple transactions together, improving speed and reducing the overall cost per transaction. According to Taiko’s website, the protocol is maximally compatible with Ethereum. Developers familiar with Ethereum can quickly deploy their applications on Taiko, leveraging the same codebase and development tools.
Taiko announced an initial airdrop phase for its native token on May 23, 2024, and on May 27, the L2 solution went live on the Ethereum mainnet. At the time of writing, Taiko’s TVL (total value locked) exceeds $14M, according to DefiLlama.
2. Scroll
Scroll scaling solution. Source: Scroll.io
Scroll extends Ethereum’s capabilities by using Zero Knowledge technology, called zk-SNARKs. It increases Ethereum’s transaction throughput and reduces costs by aggregating multiple transactions into a single batch and generating a cryptographic proof. Scroll’s compatibility with Ethereum allows Ethereum-based apps to be easily deployed onchain. The solution was launched on the Ethereum mainnet in October 2023. At the end of June, Scroll announced its Curie upgrade scheduled for July 3, with the aim of cutting gas fees by half. Over the last month, Scroll’s TVL was up by an impressive 177% and currently stands above $390M.
3. zkSync
ZKsync scaling solution. Source: zksync.io
ZKsync is a fast-growing Layer 2 chain, highly focused on decentralization, security, and lower transaction costs. The protocol was developed by Matter Labs, with its first version going live on the Ethereum mainnet in 2020. In 2022, Matter Labs launched zkSync 2.0, which was later rebranded as "zkSync Era", while the initial version (with limited use cases) was named zkSync Lite. Currently, the team continues active development of the protocol.
On June 17, an airdrop for ZKsync’s native token, ZK was held, during which 17.5% of ZK's 21 billion total token supply was airdropped to the community. ZK's airdrop, however, wasn't smooth, with many users unhappy about the airdrop rules. The reason was that only 695,232 wallets were eligible to receive the tokens, leaving a major part of active addresses without rewards, including those who seemed to meet the eligibility criteria. Answering the concerns, ZKsync published a report explaining that there were seven deciding factors on token allocation. Addresses receiving tokens included those with above-average activity, as well as community members contributing to the development, education, and advocacy of the project regardless of their network activity.
Besides the community disagreements, the airdrop faced issues from the technical side because of the high load. Finally, the challenging token allocation took place. At the time of writing, there are 3,675,000,000 ZK tokens in circulation, trading for around $0.18 and with a market cap of above $671 million.
4. Citrea
Bitcoin ZK Rollup Solution. Source: citrea.xyz
The first ZK rollup focused on Bitcoin scaling, Citrea verifies transactions off-chain relying on the security mechanism of the mainnet. It uses the Bitcoin Virtual Machine (BitVM) as a bridge between the mainnet and layer 2. Citrea is fully compatible with Ethereum, meaning Ethereum developers can build applications on the chain. On June 5, the project announced the launch of its public devnet for developers and users, who can test the network-based applications. Citrea doesn’t have a native token and uses Bitcoin for network operations. The project was developed by Chainway Labs and in February raised $2.7 M in seed funding.
5. Linea
Linea scaling solution. Source: linea.build
Developed by ConsenSys, Linea is a ZK rollup solution with native integrations with the crypto wallet MetaMask, the development suite Infura, and other tools. Initially called ConsenSys EVM, the chain was renamed Linea at the public mainnet launch in August 2023. Linea provides a developer-friendly infrastructure called Linea Build. In March 2024, the project introduced the Linea Voyage program driven by LXP (Linea Experience Points) tokens, the airdrop date of which is yet to be announced. As part of the program, token holders will be able to provide liquidity and earn rewards. At the time of writing, Linea’s TVL is over $709M, making it the largest ZK rollup at the moment.
ZK Rollup Developments in 2024
ZK rollups are still in the early stage of development. To achieve their full potential, they still need to face computational complexity and increase processing time. With new projects and existing ones launching upgrades, the sector has been seeing increasing growth. Rollups are supposed to be a part of blockchain technology’s future due to their increased privacy and enhanced transaction speed capabilities. Ethereum creator Vitalik Buterin predicted that rollups are the end game for blockchain and that all rollups will be ZK in 10 years.
Anahit Avetisyan
Author
Web3 writer and crypto HODLer with a keen interest in market trends and recent technologies.
