yearn.finance

Yearn Finance is one of DeFi's original yield aggregators — a protocol that automatically moves users' deposits between lending and yield-farming strategies to chase the best available return. It was created in early 2020 by South African developer Andre Cronje (who later also co-founded the Fantom blockchain), who first built it as iEarn to automate his own yield farming across Aave, Compound, and dYdX.

Yearn's core product is the vault (yVault). A user deposits a single asset; the vault deploys that capital into one or more strategies — supplying to lending markets, providing liquidity, or farming rewards and selling them back into the deposit asset — and the depositor receives a share token representing a growing claim on the vault's balance. Withdrawing burns the share token and returns the original asset plus accumulated yield, minus performance and management fees. Strategies are written and maintained by contributors and can be swapped as market conditions change, so users get professional yield optimization without managing it themselves.

In July 2020 Cronje distributed the governance token, YFI, with no premine, no founder allocation, and no venture-capital sale — every token went to users who provided liquidity during a short window. The tiny supply and pure distribution made YFI a landmark example of a 'fair launch' and turned it into one of DeFi's most iconic governance tokens.