Crypto exchange OKX has launched a testnet for an upcoming Ethereum layer-2 network named “X1,” according to a Nov. 14 announcement. The network is being developed using the Polygon chain development kit (CDK) and will use zero-knowledge proofs to validate deposits and withdrawals between layers.

OKX launches Ethereum layer-2 testnet using ZK-based Polygon CDK image 0 OKX exchange interface. Source: OKX

OKX is the sixth-largest centralized crypto exchange by volume, with over $1.8 billion in trading volume per day, according to data from CoinMarketCap. Its token, OKB, has a current market cap of over $3.6 billion, making it one of the top 30 cryptocurrencies. When a mainnet version of the new network is launched, OKB will be the native coin used to pay gas fees on it, the announcement stated.

X1 is being developed using the Polygon CDK, potentially making it part of the broader Polygon ecosystem that includes Polygon zero-knowledge Ethereum Virtual Machine, Polygon PoS, Near, Manta Pacific and other networks. According to the announcement, OKX will also be a core contributor to the Polygon CDK software going forward and will “invest substantial engineering resources to enhance the technology stack for Ethereum scaling solutions.”

Related: Polygon Labs and Near announce ZK prover for WASM integration

OKX chief innovation officer Jason Lau claimed that the new network will help to onboard new users to Web3, stating:

“X1 will be a key pillar of our efforts to educate and bring our users on-chain and into the world of Web3. This scalable and accessible network is perfect for developers, who can build on X1 to deliver user-friendly world-class consumer Web3 applications, all while maintaining interoperability with other networks and ecosystems.”

OKX is also the creator of OKT Chain , an Ethereum sidechain that uses OKB as its native coin. It isn’t the only exchange to build its own network: Binance launched BNB Chain in 2019 , and Coinbase launched its layer-2 “Base” network on Aug. 9 .