# Why Farcaster has chosen Optimism to scale

Source: https://warpcast.com/francos.eth/0x1e5a05

Is there any write up about the rationale behind farcaster choosing OP to scale? Really curious about what criteria was used. Might help others with similar decision.

Why OP not Arbitrum? Why an optimistic rollup vs zk rollup (evm equivalent* like zKSync, or smthng different like starknet)?