Optimistic rollup layer 2 (Base)

Base is an Ethereum layer 2 built and run by Coinbase. After a launch for developers on 13 July 2023, its mainnet opened to everyone on 9 August 2023, with transactions settled on Ethereum. It launched on Optimism's OP Stack, but on 18 February 2026 Base announced it was moving to its own Base-operated stack, and L2BEAT records it leaving Optimism's Superchain on 4 March 2026. L2BEAT lists Base as an optimistic rollup at Stage 1 that posts its data to Ethereum as blobs and uses ETH for gas. Also: Base, post of 18 February 2026