Ethereum Layer 2
Web3 / layer2 solutions
A category of scaling networks built on top of Ethereum that inherit its security while processing transactions off the main chain, then settling them in batches to reduce costs and increase throughput. Ethereum's base layer processes roughly 15-30 transactions per second and charges gas fees that can spike into dollars during high demand, making many applications impractical. Layer 2s address this by handling execution separately and periodically committing compressed data or cryptographic proofs back to Ethereum, ensuring users can always exit to the main chain. Two architectures dominate: optimistic rollups (Arbitrum, Optimism) that assume transactions are valid and use fraud proofs to catch misbehavior, and ZK rollups (zkSync Era, Scroll, Linea) that produce validity proofs for every batch. By 2025, Ethereum Layer 2s processed the majority of Ethereum-ecosystem user activity, with leading chains hosting billions in total value locked. Example: Blast launched in early 2024 as an OP Stack-based Ethereum Layer 2 with a distinctive feature: it automatically passes native yield from ETH staking and Treasury bill holdings to user wallets and smart contracts by default, reaching over $2 billion in TVL before its mainnet went live in May 2024. Why it matters for Web3: Ethereum Layer 2s have made onchain activity accessible to ordinary users by cutting transaction costs from dollars to cents while preserving Ethereum-level security guarantees. The intense competition among dozens of active L2s is driving rapid advances in rollup cryptography, sequencer decentralization, and cross-chain interoperability, effectively turning Ethereum into a settlement layer for a sprawling ecosystem of application-specific chains.
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