Rollup Basics
Before diving in, it’s important to understand what rollups are and the two primary types available. Alchemy Rollups supports both Optimistic Rollups and Zero-Knowledge (ZK) Rollups.
What is a Rollup?
A rollup is a blockchain solution that processes transactions off the main chain while using a Layer-1 blockchain for security. Instead of processing each transaction on the main chain, rollups batch transactions together and post a summary or proof to the Layer-1 network. This approach reduces fees and increases throughput while maintaining the security of the main chain.
Optimistic vs. ZK Rollups
Optimistic Rollups:
- Assume transactions are valid by default.
- Use a challenge period to allow for fraud proofs in case of invalid transactions.
- Typically have a delay for finality due to the challenge period.
- Provide strong security guarantees through economic incentives.
Zero-Knowledge (ZK) Rollups:
- Generate a cryptographic proof for each batch of transactions.
- Allow for near-instant finality since there’s no challenge period.
- Offer even greater scalability by reducing the amount of data posted to Layer-1.
- Can be more complex to implement due to the proof generation process.
Choose the framework that best fits your application’s requirements.