Offchain Labs, the team behind the highly anticipated Ethereum layer two platform, Arbitrum One, has completed the public mainnet launch of its optimistic rollups solution.

Announced on Aug. 31, Offchain Labs also revealed that it has secured $120 million in a Series B fundraising round. The round was led by Lightspeed Venture Partners and also saw participation from heavyweight crypto investors Polychain Capital, Pantera Capital, Alameda Research and Mark Cuban.

Lightspeed partner Ravi Mhatre also joined Offchain Labs’ board as part of the round. Amy Wu, also a partner at Lightspeed, stated:

“[Offchain Labs’] dedication to the Ethereum developer community is second to none and they have the best, easiest-to-use scalability product. That’s why over 400 projects have chosen to launch with Arbitrum, including Reddit.”

In May, Offchain Labs, completed its beta launch of Arbitrum One for developers, allowing developers to begin building on the platform.

Many leading DeFi protocols are already building on Arbitrum One, including Aave, MakerDAO, Chainlink, and Uniswap. Last month, popular social media network Reddit also announced it will launch its own layer-two rollup based on Arbitrum’s technology.

Offchain Labs are not alone in pushing to scale Ethereum, with rival rollups solution Optimism onboarding developers in recent weeks, while the total value locked (TVL) in decentralized finance protocols on the Polygon sidechain appears to have found a floor at $5 billion since the recent crypto downtrend.

Related: Chainlink launches data oracles on Arbitrum One’s Ethereum scaling solution

Arbitrum One’s public launch comes as gas fees have been persistently high on the Ethereum mainnet as a result of the surging popularity of nonfungible tokens (NFTs).

According to Etherscan, average gas prices have exceeded 100 gwei over the past week, with regular token transfers costing more than $7 while transactions using decentralized exchanges exceed $65 on average. By contrast, gas prices were just 15 gwei one year ago.