Chainlink Kills Functions Service, Introduces CRE for Custom API Calls

Chainlink Functions was a service that allowed smart contracts to call external APIs directly without relying on centralized servers. This addressed the 'oracle problem' where blockchains couldn't fetch data from outside sources. Chainlink's oracle network had already provided pre-configured price feeds, but developers needed custom API calls for specific use cases.

The Chainlink Functions architecture worked by having a smart contract send a request to a Decentralized Oracle Network (DON), which then executed the code and fetched data from the external API. The result was aggregated and returned to the contract. This process ensured that no single node controlled the final answer, reducing the risk of manipulation.

Chainlink Functions supported encrypted secrets for APIs that required keys, preventing developers from hardcoding sensitive information into public source code. Each request cost gas for on-chain transactions and LINK for the DON's work, but this allowed developers to access custom API data without maintaining their own backend infrastructure.