The soaring popularity of so-called "re-staking" is the latest sign of risk-taking in crypto markets as prices rally and traders hunt for yield. Bitcoin, the biggest cryptocurrency, is near all-time highs while ether, the second biggest, is up more than 60% this year.

At the heart of the re-staking boom is Seattle-based start-up EigenLayer. The company, which in February raised $100 million from U.S. venture capital firm Andreessen Horowitz’s crypto arm, has attracted $18.8 billion worth of crypto to its platform - up from less than $400 million six months ago.

EigenLayer invented re-staking to expand a long-standing crypto practice called staking, its founder Sreeram Kannan told Reuters.

Blockchains are a kind of database, which involve many computers in a network checking and confirming who owns which cryptocurrencies. To do this, owners of crypto tokens, such as ether, allow their assets to be locked up as part of the validation process.