Thread by @0xfoobar

1/ Explaining the zkEVM

- what it is
- how zk-rollups compare with other rollup types
- the competitive landscape for zk-rollup creators

And who really was first 😉

2/ A Layer-2 rollup is a way to batch user transactions together for cheaper gas costs while preserving most of the security guarantees of Ethereum mainnet.

Two main types: optimistic rollups & zk rollups

3/ Optimistic rollups such as Optimism & Arbitrum publish periodic state roots to mainnet, and rely on fraud proofs to ensure state is honest

ZK rollups such as Loopring & Starkware publish state roots to mainnet, but also include cryptographic proofs of validity

4/ ZK rollups are generally preferred for their stronger guarantees, but they're technically challenging. Developers have to write custom "circuits" in esoteric programming languages. Even tiny changes to functionality can require massive changes to the underlying circuit.

5/ This is the problem that zk-rollups like Loopring and Starkware have run into. While theoretically powerful, they're so complex that few devs can build on top of them.

So the holy grail: what if you could run arbitrary Solidity code on a zk-rollup? This is called the zkEVM 🤯

6/ Let's walk through the competitive market landscape, and call out recent bizdev marketing shenanigans

7/ Today, Polygon announced the first zkEVM

8/ Yesterday, Scroll announced the zero-th zkEVM

9/ Last December zkSync launched their live testnet, which makes them the negative-one-th zkEVM

10/ Loopring runs a zk-rollup, but it is not a zkEVM. It is purpose-built to handle a specific subset of activities such as token transfers and dex trades.

11/ Starkware runs a zk-rollup, but it is not a zkEVM. Developers must write custom logic using Cairo instead of Solidity.

12/ Setting aside who was "first", it's clear that the zkEVM holy grail is close! This is incredible news, the competition among multiple quality teams will only push innovation along faster.

13/ What does this mean for you, a nontechnical user?

Cheaper gas, more rollup options, and more apps on your favorite rollup.

Spot prices may have bull and bear markets, but technical innovation is up only 🔥

Thanks for reading, give it a share 👇