optimism

OptimismPortal2 withdrawals gated on a proven+finalized dispute game, but Guardian (Security Council) can blacklist games and pause the portal

Fault-proof dispute game requires bonded participation; griefing is bounded by escalating bonds

L2 state validity is established by the fault-proof program (Cannon MIPS) rather than a price oracle, removing classic oracle-manipulation surface

OP Mainnet live since 2021; Bedrock (2023) and fault proofs (2024) have operated at multi-billion-dollar bridge TVL with no successful mainnet exploit

L1 system contracts are upgradeable via a ProxyAdmin owned by a 2-of-2 between the Optimism Foundation and the Security Council multisig

Resistance under independent adversarial research — evidence is held private.

Very active public monorepo with strong CI, code owners, and a published security-council / pause runbook

L1<->L2 messaging via OptimismPortal2 + CrossDomainMessenger with a 7-day finalization window is the core trust path and the dominant value-at-risk surface

Deep multi-contract dependency chain: OptimismPortal2 -> DisputeGameFactory -> FaultDisputeGame -> AnchorStateRegistry -> PreimageOracle/MIPS

Upstream dependency is essentially Ethereum L1 only — minimal external-protocol upstream cascade exposure

Pinned Solidity + OpenZeppelin with a disciplined, version-locked contracts-bedrock build

Conditional: liquidation cascades, holder concentration (Gini), exit queue analysis. Active for protocols with tradeable positions.