# OP Mainnet

> Ethereum L2 and the reference OP Stack implementation, providing low-cost EVM execution and the Superchain interoperability roadmap.

- Readiness score: **76/100** (score.v2)
- Integration difficulty: low
- Chains: optimism, optimism-sepolia
- Categories: l2, settlement, execution, op-stack
- Last verified: 2026-06-02 by composewith.eth research (docs.optimism.io live-verified via WebFetch 2026-06-02; OP Stack L2 confirmed) (confidence: high)

## Resources

- docs: https://docs.optimism.io/
- sdk: https://github.com/ethereum-optimism/optimism
- template: https://docs.optimism.io/
- grant: https://app.optimism.io/retropgf

## Good for

- low-cost EVM execution
- Superchain-aligned deployments
- public-goods-funded ecosystems

## Avoid for

- apps that need a sovereign appchain with custom gas tokens

## Capabilities

### EVM execution (production-ready)
Best for: general-purpose smart contracts, low-fee transactions

## Composes with

- **uniswap** (supporting_protocol; supports) — Uniswap can provide swap and liquidity flows for OP Mainnet applications.
- **chainlink** (oracle_and_price_data; supports) — Chainlink can provide oracle and automation services for OP Mainnet contracts.
- **maci** (governance_and_voting; supports) — MACI can be used for private voting deployments on Optimism-supported environments.

## Advisories

- **Prefer viem op-stack actions over the legacy @eth-optimism/sdk** (deprecation, recommended) — The standalone @eth-optimism/sdk package is no longer the recommended way to build on the OP Stack. New deposit/withdrawal and cross-domain messaging flows should use viem's op-stack actions (or the equivalent op-stack libraries) referenced from the current OP docs. Existing integrations on @eth-optimism/sdk keep working but should plan a migration off the deprecated package.

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Canonical: https://composewith.eth/protocols/optimism · JSON: https://composewith.eth/protocols/optimism.json