Crypto exchange OKX on Monday launched the public mainnet rollout of “X Layer,” its layer 2 solution designed to link users with the Ethereum ecosystem. 

X Layer is the latest layer 2 built with the Polygon Chain Development Kit (CDK), a framework that enables developers to create blockchains based on zero-knowledge proofs. Zero-knowledge (ZK) proofs can be tapped by developers to increase privacy and improve scalability.

Read more: What Are Zero-Knowledge Proofs?

As a result of the mainnet launch, OKX’s 50 million users globally can withdraw tokens from the exchange and onto its Ethereum-linked layer 2 if they want to transact onchain — including interacting with decentralized applications (DAPPs). 

OKX’s platform token, OKB, used to pay network gas fees, increased 14% in the last 24 hours to trade at $59.15, data from CoinGecko shows. The move comes as OKX, which holds over $22 billion in crypto custody, has become the third-largest exchange by 24-hour trading volume with over $5.2 billion, behind only Binance and Bybit.

The public mainnet launch of X Layer follows in the footsteps of crypto exchanges Bybit and Coinbase releasing their own layer 2 blockchain network, Mantle and Base, respectively. Each has the aim of onboarding millions of people onchain. 

Polygon’s CEO Marc Boiron, told Unchained that more crypto exchanges would be using the Polygon CDK to build out their own layer 2 networks.

“There’s obviously some level of ‘Hey, Base is doing this, and we see Bybit doing this,’ but I think a lot of this is really just a big opportunity that exists and specifically in this ecosystem, where with Polygon you have the AggLayer that connects it all,” Boiron said. 

X Layer plugs into Polygon’s AggLayer, a protocol that enables an aggregated blockchain ecosystem to unify various layer 2 networks and allow users to move assets across chains. 

“X Layer’s connection to the AggLayer solves the fragmentation of liquidity and users across chains on the AggLayer so they can all grow together,” Boiron said in an additional statement. “OKX’s 50M users now have an easy path to onboarding to X Layer and all the other chains connected to the AggLayer.”