Scroll: A Comprehensive Guide to the New ZK-EVM

Scroll is a new zero-knowledge (ZK) Ethereum Virtual Machine (EVM) rollup that launched in October 2023. It is designed to scale Ethereum by processing transactions off-chain and then generating proofs that attest to the validity of these transactions. These proofs are then submitted to the Ethereum mainnet for verification and inclusion.

Scroll is notable for its bytecode-level EVM compatibility, which means that existing Ethereum smart contracts can be deployed on Scroll without any modifications. This makes Scroll an attractive option for developers who want to build scalable applications without having to rewrite their code.

Scroll is also notable for its decentralized sequencer, which means that there is no single entity in control of the rollup. This helps to improve the security and censorship resistance of Scroll.

How Scroll Works

Scroll works as a zero-knowledge (ZK) Ethereum Virtual Machine (EVM) rollup. This means that Scroll processes transactions off-chain and then generates proofs that attest to the validity of these transactions. These proofs are then submitted to the Ethereum mainnet for verification and inclusion.

Here is a simplified overview of how Scroll works:

1. Users submit their transactions to a sequencer.

2. The sequencer bundles the transactions together and executes them off-chain.

3. The sequencer generates proof that attests to the validity of the transactions.

4. The proof is submitted to the Ethereum mainnet.

5. The Ethereum mainnet verifies the proof and includes the transactions in the next block.

Scroll uses a variety of techniques to improve its scalability and security. For example, Scroll uses zk-SNARKs (zero-knowledge succinct non-interactive arguments of knowledge) to generate proofs. zk-SNARKs are a type of cryptographic proof that allows Scroll to prove that a transaction is valid without revealing any of the underlying data.

Scroll is also EVM-compatible, which means that existing Ethereum smart contracts can be deployed on Scroll without any modifications. This makes Scroll an attractive option for developers who want to build scalable applications without having to rewrite their code.

Security

Scroll is secured by the Ethereum mainnet. This means that users’ funds are as safe on Scroll as they are on Ethereum.

Scroll uses many techniques to improve its security, including:

● zk-SNARKs: zk-SNARKs allow Scroll to prove that a transaction is valid without revealing any of the underlying data. This helps to protect user privacy and prevent fraud.

● Decentralized sequencer: Scroll uses a decentralized sequencer, which means that there is no single entity in control of the rollup. This helps to improve the censorship resistance of Scroll.

● Ongoing audits: Scroll is regularly audited by independent security firms. This helps to ensure that the code is secure and that there are no vulnerabilities.

Benefits of Using Scroll

Lower transaction fees: Scroll offers significantly lower transaction fees than Ethereum mainnet. This is because Scroll bundles transactions together and processes them off-chain.

Faster transaction speeds: Scroll transactions are processed much faster than Ethereum mainnet transactions. This is because Scroll does not have to wait for every block to be confirmed before processing transactions.

Increased scalability: Scroll can handle a much higher volume of transactions than Ethereum mainnet. This is because Scroll bundles transactions together and processes them off-chain.

Security: Scroll is secured by the Ethereum mainnet. This means that users’ funds are as safe on Scroll as they are on Ethereum.

EVM compatibility: Scroll is EVM-compatible, which means that existing Ethereum smart contracts can be deployed on Scroll without any modifications. This makes Scroll an attractive option for developers who want to build scalable applications without having to rewrite their code.

Rhythm of Scroll

Since its launch almost a year ago, scroll has amassed ~39M in TVL, while averaging 1.03 in TPS — which is pretty low, when compared to Ethereum’s 13.27. L2s are meant to scale Ethereum, so it makes little sense for Ethereum to have a higher TPS. Although, L2s have a higher TPS than Ethereum when combined. L2s are like 5 Ethereum’s currently.

Scroll is currently a stage 0 rollup as it still has 3 of its 5 slices of the pie red. For a rollup starting, that is fair. I expect it to move to yellow and then green as the tech stack is fully built out.

Scroll has ~$17m in TVL in DeFi, which is pretty impressive. That’s like a 50% utilization rate — to borrow a term from lending protocols. About half of Scroll’s TVL isn’t just sitting idle, it’s been used in DeFi. Contrast that to zkSync Era which has a TVL of ~$460m, with $117 of that in DeFi, resulting in a utilization rate of 25%.

The requirements to use Scroll

1. A wallet: If you use Metamask, TrustWallet etcetera. You can use ChainList to add the Scroll network to your favourite wallet.

2. Some ETH: As with every layer 2 out there (except mantle), Scroll uses ETH to pay for gas — for transacting or bridging.

How to bridge to Scroll

To bridge ETH to Scroll, the starting point is the native Scroll bridge.

Steps:

1. Visit the [Scroll Bridge](https://scroll.io/bridge) website and connect your wallet.
2. Select the token you wish to bridge and enter the amount you want to bridge.
3. Click Deposit Funds.
4. Follow the on-screen instructions to approve the transaction.
5. Once the transaction is confirmed, your assets will be deposited into the Scroll bridge.
6. Once the deposit has been processed (this can take up to 10 minutes), you will be able to withdraw your assets to Scroll mainnet.

To withdraw your asset from Scroll back to Ethereum’s mainnet follow the same steps.

What to do on Scroll

The best place to go that serves as the top of the funnel if you want to try out stuff on Scroll is their ecosystem. There’s not much there, seeing Scroll is less than a month old. But here are some notable apps to check out — of course these are not endorsements, let alone financial advice.

● KyberSwap: Not only is it the largest DEX on Scroll, but it’s also the largest protocol, boasting a TVL of ~$5m.

● AlienSwap: A multi-chain NFT marketplace and aggregator.

● Scroll Kingdoms: Scroll Kingdoms is a cross-chain free-to-play MMORPG.

Conclusion

Scroll is a promising new ZK-EVM solution with the potential to revolutionize the Ethereum ecosystem. It offers users significant cost and speed benefits over Ethereum mainnet, making it an attractive option for a wide range of applications.

In this guide, we have covered the basics of using Scroll, including how to bridge assets to Scroll, how to interact with dApps on Scroll, and how to withdraw assets from Scroll.

If you’re looking for a way to save money on gas fees and get faster transaction speeds, then Scroll is the solution for you.