Overview
Chainlink is a decentralized oracle network that connects smart contracts to real-world data, APIs, and payment systems. Launched in May 2019 with the LINK token, it is the most widely used oracle solution in DeFi, providing price feeds that power lending, derivatives, and stablecoins. Its network of node operators aggregates data to resist manipulation.
How It Works
Chainlink node operators fetch data from multiple independent sources, aggregate the values, and publish them on-chain as price feeds. The network uses reputation and staking to align node behavior, and its decentralized structure means no single operator controls the data. Smart contracts read these feeds to execute liquidations, set rates, and settle positions, relying on the feeds being accurate and timely.
Why It Matters
Reliable price data is the foundation of DeFi risk management, and Chainlink's feeds became the default trust layer for it. The project expanded into cross-chain interoperability, verifiable randomness, and data streams, making it a broad infrastructure provider. Its concentration of critical data dependency also raises the question of what happens when a widely used oracle is compromised.
Related Concepts
Chainlink is an Oracle network underpinning DeFi protocols like Aave and Compound. It is central to price feed security and is connected to concepts like Flash Loan manipulation risk and the broader data infrastructure of Web3.