How to add zkSync to MetaMask
The easiest way to add the zkSync Network to your MetaMask account is with the Chainlist application. Chainlist is a comprehensive list of EVM networks that collects all of the verified RPC endpoints and allows users to add any network to their MetaMask Wallet.
All you need to do is search for 'zkSync' in the 'Search Networks' tab and make sure that you have 'Testnets' highlighted because zkSync is still in beta. Once you complete this step, you will see the zkSync alpha testnet which you can add to MetaMask and you will be automatically connected.
What is zkSync?
zkSync is one of the most popular zk-rollups currently in development. It is a scaling solution that utilizes zero-knowledge proofs to keep the data associated with each transaction private, while still being able to verify the correctness of the entire blockchain. This enables zkSync to offer much higher throughput than other solutions like Plasma or Optimistic Rollups, as well as significantly lower fees.
zkSync uses a new transaction format that allows users to batch multiple transfers into a single compacted transaction, called an "account update." This means that instead of having to create and sign several different transactions (one for each transfer), users can condense those same transfers into a single account update. Not only does this reduce the amount of data that needs to be sent to the network, but it also allows for more efficient verification by the network itself.
What are Zero Knowledge Proofs?
A zero-knowledge proof is a method by which one party (the prover) can prove to another party (the verifier) that they know a certain piece of information, without revealing what that information is. This is useful in the context of cryptocurrencies because it allows a user to prove that they own a certain amount of coins without having to reveal their private keys.
Is zkSync Safe?
zkSync is still in development and has not yet been audited. However, the team behind zkSync has published a comprehensive security analysis of their protocol which you can find here. In addition, the team is planning to open source their code once the mainnet launches, which will allow the community to review the code and ensure that it is secure.