Linea Documentation

Linea Yield Boost is a protocol-level mechanism that converts idle bridged ETH into ecosystem incentives. It works by programmatically staking a portion of ETH held in the LineaRollup using Lido v3 stVaults on Ethereum Mainnet.

Key Benefits:

• Replaces temporary emission-based rewards with sustainable, Ethereum-native yield.
• Reduces reliance on mercenary liquidity.
• Strengthens the Linea ecosystem by redirecting staking rewards to a distributor contract on L2 to incentivize liquidity providers and DeFi protocols.

Note on Status: Yield Boost is in a phased rollout. Initial infrastructure (including YieldManager and StakingVault) has been deployed on mainnet, but some components may not yet be active.

Linea provides two primary interfaces for interacting with the network:

1. JSON-RPC Interface: Used for reading and writing blockchain data (e.g., querying state, sending transactions).
2. Token API: A specialized API used to retrieve token metadata and user balances.

For detailed technical specifications, refer to the JSON-RPC API reference and the Token API documentation.

The Linea bridge app (https://linea.build/hub/bridge) offers three primary methods for moving funds onto the Linea network:

1. All bridges (Bridge aggregator): Powered by Li.Fi, this is the best option for most users. It supports numerous EVM chains and Solana. It automatically selects optimal routes based on your priority (speed or price) using DEXs and bridges. It is generally faster than the native bridge but may have slightly higher costs.
2. Native bridge: Built by the Linea team to interface with the canonical token bridge. It is best suited for tech operators, protocols, or moving large liquidity, and is the only option for testnet bridging.
3. Buy: A fiat onramp aggregator provided by Onramper, allowing you to purchase funds directly onto Linea.

Linea Yield Boost is a protocol-level mechanism on the Linea Public network designed to automatically stake a portion of the ETH held in the LineaRollup contract.

How it works:

1. Users bridge ETH from Ethereum (L1) to Linea (L2) via the LineaRollup.
2. This ETH remains on L1 and is programmatically deposited into a Lido v3 StakingVault on Ethereum Mainnet.
3. The resulting beacon chain staking rewards are distributed back into the Linea ecosystem to incentivize liquidity providers (LPs) and support DeFi protocols.

Note: As of the current documentation, Yield Boost is not yet live and describes an intended design.

The sequencer is the core component of the Lineth execution client. It is responsible for ordering, building, and executing blocks to facilitate the generation of Zero-knowledge (ZK) proofs.

To prevent DDoS attacks, the sequencer is not directly accessible from outside the network; instead, it communicates with RPC nodes via a P2P connection.

The Linea Tracer is a plugin for Linea Besu that runs as part of the Linea sequencer. Its primary purpose is to generate the execution data required by the prover to create Zero-knowledge (ZK) proofs.

Core Responsibilities:

• Execution Trace Generation: During block processing, the tracer captures granular data (traces) representing the operations performed by the Ethereum Virtual Machine (EVM) for each transaction.
• Batch Size Calculation: It provides trace counts used to calculate the size of batches.
• Prover Input Preparation: It creates conflated trace files which serve as the direct input for the prover to generate execution proofs.

Lineth (formerly the Linea Stack) is a collection of protocol components, onchain contracts, and operational capabilities designed for operators to deploy and run their own Layer 2 or Layer 3 networks. It inherits a Zero-knowledge proof (ZK proof) system and provides an Ethereum-compatible execution environment.

Key capabilities include:

• Cost and Speed: Reduced transaction costs compared to Ethereum L1 and near-instant soft finality via 1s block times.
• Interoperability: Ethereum-anchored interoperability using rollup and bridge components to access Ethereum liquidity and the DeFi ecosystem.
• Customization: Flexible deployment models allowing for specific privacy, compliance, and data availability (DA) requirements.
• Operational Control: Clearly defined components and failure boundaries for managing risk, uptime, and compliance.

Linea Mainnet is a public, permissionless zkEVM Layer 2 (L2) network built on Lineth.

Key Characteristics:

• Security: Inherits Ethereum's security and decentralization while increasing throughput and reducing fees.
• ZK Proof Technology: Uses ZK proofs instead of fraud proofs, removing the seven-day lockup period and allowing for instant, cost-free withdrawals.
• EVM Equivalence: Fully compatible with the Ethereum Virtual Machine (EVM), allowing Ethereum-based projects and assets to be deployed without code changes.
• Fast Finality: Provides soft finality within 1s due to short block times and a lack of L2 transaction reorgs.
• Predictable Pricing: Offers clarity on transaction costs and how L1/L2 costs are accounted for.
• Recoverable State: Supports reconstructing Linea's state at the last point of finalized data via a dedicated plugin.