Scroll is a ZK-rollup that prioritizes maximum EVM compatibility — describing itself as “bytecode-level EVM equivalent.” Co-founded by Sandy Peng and Ye Zhang (both with prior connections to the Ethereum Foundation’s Privacy and Scaling Explorations team), Scroll is notable for its close collaboration with Ethereum Foundation researchers rather than a purely private-sector approach. Launched on mainnet in October 2023, Scroll is classified as a Type 2 zkEVM — compatible with the Ethereum state model and most EVM tooling without smart contract modification. It uses a multi-layered proving architecture (zkEVM + recursive aggregation) to efficiently batch proof verification on Ethereum.
Type 2 zkEVM
Vitalik Buterin’s zkEVM taxonomy (2022):
| Type | Description | Example | Tradeoff |
|---|---|---|---|
| Type 1 | Fully Ethereum-equivalent (prove actual Ethereum) | None complete yet | Very slow proving |
| Type 2 | EVM-equivalent (same state model, same opcodes) | Scroll, Polygon zkEVM | Slower, larger proofs |
| Type 3 | Most EVM compatible | zkSync (partial) | Faster proving |
| Type 4 | High-level language only | Starknet (Cairo) | Most efficient proving |
Scroll as Type 2:
- Executes Ethereum opcodes identically
- Same gas cost structure as Ethereum
- Existing Solidity/Vyper contracts deploy without modification
- Smart contract addresses are the same format
- Developer toolchain: Hardhat, Foundry, Remix all work natively
The tradeoff: Proving an EVM execution exactly is more computationally intensive than proving a custom VM (Type 4). Scroll accepts slower proof generation in exchange for maximum compatibility.
Proving Architecture
Scroll uses a multi-layer proving system:
- zkEVM Prover: Proves that the EVM executed correctly for a batch of transactions. Generates sub-proofs for each execution unit (arithmetic, memory, bytecode, etc.)
- Aggregation Layer: Aggregates multiple zkEVM sub-proofs into a single compact proof
- Ethereum Verifier: Single proof submitted to an Ethereum smart contract for final verification
Key contributors:
- PSE (Privacy and Scaling Explorations) — Ethereum Foundation team contributed to the zkEVM circuit design (Halo2 proof system)
- Scroll’s proving system is based on Halo2 (developed by Zcash/Electric Coin Co.) rather than Groth16 or PLONK
Halo2:
Halo2 is a PLONK variant that removes the trusted setup requirement through a different polynomial commitment scheme (IPA – Inner Product Argument). Scroll’s use of Halo2 gives it a similar “no trusted setup” advantage to STARKs while maintaining smaller proof sizes.
Ethereum Foundation Connection
Scroll’s origin is close to Ethereum’s research community:
- PSE collaboration: The EF’s PSE team worked directly with Scroll on zkEVM circuit development; some early Scroll work was done in coordination with PSE researchers
- Open source: Scroll publishes its zkEVM circuits and provers as open-source repositories; other projects can study and build on them
- Research alignment: Scroll targets Type 2 EVM compatibility because it most closely aligns with Ethereum’s long-term roadmap (The Verge: making Ethereum itself ZK-proof-verifiable)
Scroll vs. Competitors
| Rollup | Type | Proof System | EVM Compatibility | Status (2024) |
|---|---|---|---|---|
| Scroll | Type 2 | Halo2 | Bytecode-equivalent | Live |
| Polygon zkEVM | Type 2 | PLONK/fflonk | Bytecode-equivalent | Live |
| zkSync Era | Type 3/4 | PLONK (Boojum) | Compiler-level | Live |
| Starknet | Type 4 | STARK | Cairo only | Live |
| Linea (Consensys) | Type 2 | PLONK + custom | EVM compatible | Live |
Ecosystem
Scroll attracted many Ethereum ecosystem protocols at launch:
- DEXes: SyncSwap (deployed on Scroll), Ambient Finance, SpaceFi
- Lending: AAVE v3 deployed on Scroll; LayerBank
- Bridges: Stargate, Orbiter Finance, Relay
- Stablecoins: USDC, USDT, native bridged from Ethereum
Transaction Economics
Scroll’s gas model:
- Users pay L2 gas (execution cost) + L1 data posting cost (calldata compressed and posted to Ethereum)
- ZK proofs enable data compression beyond what Optimistic rollups achieve
- Typical Scroll transactions: 10-50x cheaper than Ethereum mainnet
- No withdrawal delay (unlike 7-day delay on Optimistic rollups) — ZK validity proofs allow faster finalization
How to Use Scroll
- Add Scroll to MetaMask:
Network: Scroll Mainnet
RPC: https://rpc.scroll.io
Chain ID: 534352
Token: ETH - Bridge ETH from Ethereum at scroll.io/bridge (~20 min via official bridge)
- For faster bridging: Orbiter Finance or Relay.link
- Deploy Solidity contracts: add Scroll network to Hardhat/Foundry config; no code changes needed
Acquire ETH via . Scroll is Ledger-compatible via MetaMask — secure with .
Social Media Sentiment
Scroll has strong credibility among Ethereum developers and researchers due to its open-source approach and EF collaboration. Developer feedback on bytecode compatibility is generally positive — teams report deploying existing Ethereum contracts with zero modifications. The criticism: Scroll has been slower to ship compared to zkSync Era and Starknet (which launched earlier) and has not run a native token or airdrop as of mid-2024, creating speculation about a potential future token distribution. The lack of token creates lower retail speculative interest vs. competitors who had already airdropped. Ethereum Foundation-affiliated projects have a reputation for technical seriousness but slower commercial execution, and Scroll broadly fits this pattern.
Last updated: 2026-04
Related Terms
Sources
Ben-Sasson, E., Bentov, I., Horesh, Y., & Riabzev, M. (2018). Scalable, Transparent, and Post-Quantum Secure Computational Integrity. IACR Cryptology ePrint.
Bowe, S., Grigg, J., & Hopwood, D. (2019). Halo: Recursive Proof Composition Without a Trusted Setup. IACR Cryptology ePrint.
Buterin, V. (2022). The Different Types of ZK-EVMs. Vitalik.ca.
Gabizon, A., Williamson, Z. J., & Ciobotaru, O. (2019). PLONK: Permutations over Lagrange-bases for Oecumenical Noninteractive arguments of Knowledge. IACR.
Thibault, L. T., Jobin-Piché, M., & Bhatt, D. (2022). Blockchain Scalability and Its Foundations in Distributed Systems. IEEE Access.