The first large minting of MakerDAO’s dai stablecoin using a bitcoin synthetic has occurred, signaling user demand for inter-blockchain asset support on Ethereum’s largest decentralized finance (DeFi) protocol.

Crypto lending platform Nexo minted $4 million dai Wednesday by using WBTC as collateral. 

WBTC, an ERC-20 token created by placing deposits of bitcoin with crypto custodian BitGo, was approved as collateral on the MakerDAO platform on May 3. Launched in January 2019, WBTC’s market cap is currently $21.7 million, according to DeFi Pulse.

“This really showcases the latent demand for non-ETH assets,” MakerDAO founder Rune Christensen said in a tweet, “and it’s the beginning of a broader trend of DeFi acting as an economic vacuum that will eventually attract almost all value to the ethereum blockchain.”

Adding exposure to bitcoin is a major step by DeFi’s leading protocol, giving Maker lenders access to the largest cryptocurrency by market cap for further issuance of dai-based loans.

Read more: The CoinDesk 50: MakerDAO Is the Godzilla of DeFi

Calls to add bitcoin onto the protocol have floated around the Maker community before but gained steam following the flash crash of ether (ETH) on March 12. At the time, Maker community members considered adding bitcoin, stablecoins and even tokenized gold as collateral assets to protect against further plunges in ETH’s price. 

The community eventually added support for USD Coin (USDC), which largely alleviated dai’s dollar peg issues during the month of April. Yet, the wheels were in motion for the addition of bitcoin – as demonstrated with the early April addition of an ETH/BTC pricing feed on MakerDAO. 

Some DeFi developers also believed porting bitcoin onto Ethereum would be a win-win: DeFi users could gain exposure to bitcoin’s liquidity – such as derivatives platform dYdX –  while utilizing Ethereum’s transaction speeds. And, as the oldest and largest DeFi protocol, the addition of bitcoin to Maker would pave the way for bitcoin onto Ethereum in general. 

The WBTC-generated dai could be used for a variety of purposes, data scientist Alex Svanevik said in a Medium post last week, including lending the dai at interest. 

The initial WBTC minting took place on token sale platform CoinList, with Nexo minting 999.6 WBTC May 11. Those funds were then moved to Maker compatible wallet Oasis in two transactions of 1 WBTC – perhaps as a test – and 997 WBTC on May 13 and May 20, respectively. (Nexo did not return a request for comment.)

Read more: Why MakerDAO Should Consider Negative Interest Rates for Dai

The minting of $4 million in stablecoins represents some 3% of the amount of dai currently minted, but about 50% of the WBTC market cap, according to DeFi Pulse. 

WBTC isn’t the only tokenized bitcoin competing for space on Maker. Keep’s tBTC was working on a listing on the DeFi protocol before pausing operations after a bug was found in the protocol less than a week after it launched.