Hello Celo community and cLabs team! We at the Optimism Foundation are really excited at the prospect of this proposal. Unsurprisingly, we agree that building as an Ethereum L2 could accelerate Celo’s mission. We’re optimistic (
) that the real-world, human-centric ethos of your community will continue to benefit the Ethereum movement at large.
We’re also happy to see you choose the OP Stack to build with, and your proposed improvements are super exciting. As such, we’d like to point out some of the positive-sum ways we can collaborate. The OP Stack is an MIT-licensed public good, and we will always defend your right to do whatever you wish with it–but, if we practice good mutual modularity, we can all benefit from shared improvements and avoid redundant work.
The modular sequencing interfaces for the OP Stack are in active research and development. We currently have an active Request for Proposals to build an MVP of leader election in the OP Stack, and have accepted one proposal by the Espresso team to date. This milestone is only for a round-robin sequencing scheme, but the goal is to produce a generalized inbox and batching interface which could easily integrate solutions like Celo’s pBFT. We would encourage your communication/collaboration with the Espresso team as they work on their proposal, and welcome sharing any learnings from your own efforts.
We have similar plans for alternative data availability providers–though this is not at the stage of public RFP, our thinking is progressing rapidly and we’ll have more to share in the coming months. There’s a lot we, and the broader community, can learn from your approach to alt-DA. We’d love to leverage your expertise, collaborate on the process, and hopefully create standards for additional projects in the Optimism Collective to build from.
Thanks again–we’re looking forward to keeping the conversation open as your work progresses, and to a bright future together. 
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