Optimism Bedrock vs Scroll: EVM Compatibility

Proven compatibility: Implements full EVM equivalence, running the standard Geth execution client. This means near-zero code changes for existing dApps (e.g., Uniswap, Aave). This matters for protocols prioritizing immediate, risk-averse migration from Ethereum L1.

Mature ecosystem: Integrated with the dominant OP Stack toolchain (Foundry, Hardhat plugins) and the Superchain vision. This matters for teams wanting standardized deployment and future interoperability with chains like Base and Zora.

Deep technical alignment: Achieves compatibility at the bytecode level, not just the EVM spec. This ensures higher fidelity for complex, low-level operations and edge cases. This matters for developers of advanced DeFi primitives or novel VMs who need absolute precision.

Inherently secure scaling: Uses zero-knowledge proofs (ZKPs) for state transition validity, inheriting Ethereum's security via cryptographic verification. This matters for institutions and high-value applications where the strongest possible L1 security guarantees are non-negotiable.

Current performance lead: With Bedrock's optimized batch compression, average transaction fees are ~$0.01 with ~2 minute finality. This matters for consumer dApps and high-frequency traders needing the best current user experience and cost structure.

Long-term scalability path: ZK-rollups are the endgame for scaling; Scroll's architecture is built for exponential proof efficiency gains. This matters for CTOs with a 3-5 year roadmap who are betting on ZK technology winning the L2 race.

Implements full EVM equivalence at the protocol level, including the Engine API and execution/consensus client separation. This means Bedrock nodes can run standard Geth with minimal modifications. This matters for protocols requiring deep client compatibility or those migrating from Ethereum mainnet, as it minimizes integration risk and leverages existing tooling like Hardhat and Foundry.

Leverages a battle-tested, multi-round fraud proof system (Cannon) secured by a permissionless validator set. This provides strong economic security for the chain's state transitions. This matters for high-value DeFi applications (e.g., Aave, Uniswap V3) where the cost of a successful fraud must be prohibitively high, ensuring capital safety.

Achieves bytecode-level EVM compatibility through a zkEVM, meaning it executes the exact Ethereum Virtual Machine bytecode. This matters for developers seeking maximal compatibility with obscure EVM opcodes and precompiles, ensuring that even complex, legacy smart contracts (e.g., certain yield strategies) deploy without modification.

Inherits cryptographic security from Ethereum via validity proofs, with state finality achieved upon proof verification on L1 (~10-20 mins). This matters for applications prioritizing trust-minimized withdrawals and censorship resistance, as security does not rely on a live, honest validator assumption post-proof submission.

Currently employs a centralized sequencer operated by the OP Labs team. This creates a single point of failure for transaction ordering and liveness. This matters for protocols with extreme decentralization requirements, as it introduces a trust assumption and potential MEV extraction vector that is not permissionless.

ZK proof generation is computationally expensive, leading to higher operational costs for the network and potentially higher fees during congestion. Proving latency also adds to the time-to-finality. This matters for ultra-low-latency applications (e.g., HFT, gaming) where sub-second finality and minimal fee volatility are critical.

Deep Ethereum alignment: Uses a modified Geth client for its execution layer, ensuring near-perfect compatibility with core Ethereum tooling (Hardhat, Foundry, Ethers.js). This matters for teams migrating large, complex dApps from Ethereum Mainnet who need minimal code changes and can leverage existing devops pipelines.

True byte-for-byte compatibility: Scroll's zkEVM executes Ethereum bytecode directly without transpilation, supporting precompiles and edge-case opcodes. This matters for deploying protocols with complex, low-level assembly (e.g., certain DeFi optimizers or privacy tools) that break on less-compatible L2s.

ZK-proof verified finality: Transactions are finalized on Ethereum L1 in ~10-15 minutes via validity proofs, eliminating the need for a fraud challenge window. This matters for exchanges, payment networks, and bridges requiring strong, rapid guarantees without relying on watchdogs or a 7-day withdrawal delay.

No proof generation cost: As an Optimistic Rollup, it avoids the significant computational expense of generating ZK proofs for every block. This matters for keeping transaction fees consistently low for general-purpose dApps and users, as seen in its sub-$0.10 average transfer cost.

ZK-proof generation bottleneck: Proving requires expensive GPU/ASIC infrastructure, creating centralization pressures for sequencers/provers and potentially higher fee volatility during congestion. This matters for protocols needing predictable, ultra-low fee economics or those concerned with validator decentralization.