Decentralized-finance (DeFi) lending protocol Euler Finance has bounced back from last year’s $200 million exploit with a more flexible version of its cryptocurrency vault-enabled lending platform: Euler v2.

Like the first version of the protocol, Euler v2 allows users, in a non-custodial fashion, to deposit assets for lending, and other users to deposit collateral, take out loans and pay interest to the lenders.

Following the Lego-like power principle of DeFi, the new system combines building blocks like Euler Vault Kit (EVK), which empowers builders to deploy and chain together their own customized lending vaults in a permissionless manner, and an Ethereum Vault Connector (EVC), which enables vaults to be used as collateral for other vaults, the company said in a press release.

“The Euler Vault kit is a very abstract, agnostic developer's kit, for building your own lending markets,” Euler CEO Michael Bentley said in an interview. “Alongside that, the Ethereum Vault Connector is a communications protocol, like TCP-IP is to the internet. We would argue you could probably build any pre-existing lending protocol or any future lending protocol with Euler v2.”

It’s a plucky response from Euler, which suffered an exploit in March of 2023, which saw close to $200 million in crypto lost from the DeFi platform. The attacker, who used a flash loan to steal the funds, later returned them with an apology.

Bentley pointed out that Euler v2 has been in the pipeline long before the exploit happened last year, but there will be a belt and braces approach to security auditing before the new version goes live around Q2 this year.

“Euler v1 was a really heavily audited lending protocol,” Bentley said. “But there are a few extra things v2 will incorporate prior to launch, one of which is a code audit competition that really allows potentially hundreds of white hats to come in and review the code before it goes live. And even before auditing the code, we invited a whole bunch of security professionals inside to review our practices.”