Optimism ¹

What is Optimism?

Ethereum rollup that pioneered the modular OP Stack, now powering multiple chains including Base. Unlike pure speed-focused competitors, Optimism emphasizes public goods funding and building an interconnected "Superchain" of compatible L2s. The key difference: Optimism's open-source OP Stack enables other chains to join a unified ecosystem (Base, Mode, Frax) while funding builders through RetroPGF — $3.3B allocated to reward impactful contributions.

Best for: Projects wanting to build on or launch their own L2, public goods builders seeking retroactive funding, apps needing interoperability across OP Stack chains.

Technical: Optimistic rollup with 7-day fraud proof window, modular OP Stack architecture, and governance-driven public goods funding via RetroPGF.

• Security & Data Availability

  • Optimistic rollup: transactions execute off-chain, posted to Ethereum with ~7-day fraud proof window.
  • Fault proof system is active — state transitions can be challenged by any participant.
  • Posts full calldata to Ethereum using blob transactions (EIP-4844), no external DA layer.

• Infra & Execution

  • Uses op-geth and op-node stack with ~2s block times.
  • Modular OP Stack architecture enables other chains to deploy compatible L2s.
  • Sequencer is centralized; proposer and validator decentralization planned.

• Performance

  • Handles significant daily volume with established DeFi ecosystem.
  • Withdrawal finality requires 7-day challenge period.
  • Cost and throughput tied to Ethereum blob pricing and L1 congestion.

• Use Cases

  • DeFi powerhouses: Velodrome (native DEX, $130M+ TVL), Synthetix ($274M TVL), Aave V3 ($161M TVL)
  • Superchain builders: Base (Coinbase), Mode, Frax launching on OP Stack
  • Public goods projects: 643+ projects funded via RetroPGF, including dev tools and governance infra
  • Cross-chain apps: Projects leveraging Superchain interoperability

• Trade-offs

  • Sequencer centralization persists — censorship risk at the inclusion level.
  • 7-day withdrawal delay vs instant finality of zkEVMs.
  • Fault proofs rely on honest challengers — subject to liveness assumptions.
  • Superchain vision still developing — cross-chain communication limited.

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