Announcing Lineth: a production-grade ZK rollup stack joins Linux Foundation Decentralized Trust

Today, we are excited to announce that the open source Linea Stack is joining Linux Foundation Decentralized Trust (LFDT) as an incubating project under a new name: Lineth. In production since 2023, it is now moving into a vendor-neutral open source home designed for long-term technical stewardship and broader community participation.

What is Lineth?

Lineth is a production-grade, EVM-equivalent zk-rollup stack for Ethereum. It covers the full Layer 2 pipeline. The execution is built on Besu with L2-specific plugins. The block production is ensured using the Maru consensus client. The coordinator orchestrates the finalization pipeline between the sequencer, the prover, and the L1 contracts. The prover generates zero-knowledge proofs for transaction batches, relying on gnark as an upstream dependency. The arithmetization specifies and implements the zkEVM ISA constraints and includes the execution tracer that the prover consumes. Onchain contracts on Ethereum verify proofs, record finalized state roots, and support generic cross-chain messaging and token bridging between layers.

In practice, Lineth is both the foundation of the public Linea Mainnet network and the stack that developers and operators can use to launch their own Ethereum-compatible networks

Correctness is enforced through validity proofs rather than fraud windows. Transaction batches executed on L2 are proven using zero-knowledge proofs, and the L1 finalization contract verifies those proofs before accepting new L2 state roots. A detailed technical specification of the components and the proof system is available in the architecture document in the repository.

Core features

Execution

• EVM-equivalent execution built on Besu with L2-specific plugins; supports Ethereum hardforks up to and including Osaka (Fusaka).
• Full EVM equivalence provides support for all EVM clients (including Geth, Erigon, Nethermind, Reth, etc.), allowing the community to leverage what it has been building for over 10 years at the execution layer.
• Plugin surface for L2-specific gas accounting, transaction selection, and trace generation feeding the prover.
• Custom JSON-RPC namespaces for L2 concerns (gas price estimation, atomic bundles, L2 type2 state) alongside full mainnet JSON-RPC parity.

Consensus and sequencing (Maru)

Maru is the consensus client, responsible for coordination, sequencing, and block production.

• The consensus algorithm is based on QBFT with as low as 1-second block time, leveraging Consensys’ and Besu's experience in developing QBFT for enterprise networks.
• It has been designed for evolution toward multi-operator sequencing without a hard fork of the execution layer.
• It can be configured to provide instant soft finality at every block, preventing reorgs on the L2.

The Finalization Stack

The coordinator orchestrates the finalization pipeline between the sequencer, the prover, and the L1 contracts. It manages batch construction, proof requests, and L1 submission. The coordinator publishes EIP-4844 blobs with a high degree of configuration, allowing for optimizing latency or gas costs.

The prover generates zero-knowledge proofs for transaction batches, relying on gnark as an upstream dependency. It includes recursive proof composition with the final proof verified by an onchain Solidity verifier.

The arithmetization specifies and implements the zkEVM ISA constraints and includes the execution tracer that the prover consumes. It’s built using open specification under Apache-2.0 and is reviewable independent of the prover implementation. It’s designed to track EVM equivalence as Ethereum hard forks land.

Onchain contracts

Onchain contracts on Ethereum verify proofs, record finalized state roots, and support messaging and token bridging between layers.

Built for enterprise deployment

Lineth is not a research codebase being hardened for production — it is the stack that has secured Linea Mainnet since 2023, and is now in a vendor-neutral home.

Production track record

• In continuous production on Linea Mainnet since July 2023.
• 300M transactions finalized to Ethereum, 416k proofs generated
• 99.98% sequencer uptime over the last 12 months
• Up to $2.5B secured TVL, after 40 incremental rounds of audits

Open governance and licensing

• Licensed under both Apache-2.0 and MIT across the donated components, compatible with the rest of the LFDT ecosystem.
• Hosted under LFDT governance with a Technical Steering Committee and 30 proposed maintainers.

Standards alignment and EVM equivalence

• EVM-equivalent execution built on Besu with L2-specific plugins; supports Ethereum forks as they are developed, currently on Osaka (Fusaka).
• JSON-RPC parity with Ethereum mainnet; compatible out of the box with Hardhat, Foundry, viem, ethers, and standard block explorers.
• Onchain verifier and bridge contracts follow L2Beat Stage criteria and have been audited by OpenZeppelin, Diligence, and Cyfrin, with reports available here.

Operational readiness

• Deterministic, versioned releases and reproducible builds.
• First-class observability: Prometheus metrics and structured logs across the Lineth Stack.

Deployment modes

• Public L2 mode, as operated on Linea Mainnet and Linea Sepolia.
• Operator-run mode: institutions and consortia can launch their own Ethereum-compatible networks from the same codebase, including permissioned configurations for closed groups of participants in a Validium configuration.
• Besu plugins can be used to customize the chain's behavior and support various Enterprise capabilities without compromising its EVM equivalence.

Roadmap

Lineth arrives with a live technical roadmap. The main directions for the next twelve months:

• Q2
• L2Beat Stage 1. Protocol-enforced forced transaction inclusion on L1 and a permissionless escape hatch, shipping May 2026.
• Trustless interoperability. Cross-rollup messaging based on ERC-7888, with L1 state roots embedded and cryptographically proven via storage proofs, without external validators.
• Q3
• RISC-V prover transition. Moving from direct EVM arithmetization to a RISC-V zkVM. This gives the proving stack a more flexible target, simplifies tracking Ethereum hard forks, and aligns with the broader Ethereum zkVM direction.
• Full Ethereum compatibility (Type-1). Proving over the same storage structure, trie layout, and state root format as Ethereum L1.
• Q4
• Performance. Ongoing prover work targeting real-time proving by Q3 2026, which directly reduces operating costs. On the execution side, closing the gap to state-of-the-art Ethereum client performance (>30,000 transfers/sec).

Get involved

Lineth enters LFDT with 30 proposed maintainers and a clear intention to broaden that base over time. The project commits to monthly public community calls, LFDT Discord for real-time engagement, and GitHub Issues as the primary system of record for technical discussion and work tracking.

Our first community Technical Deep Dive is coming soon. Whether you're evaluating the stack for an enterprise deployment or looking to contribute, this session is your entry point. A detailed agenda with session timings is on the way. Register for Lineth Technical Deep Dive: Inside the Production-Grade ZK Rollup Stack here. 

If you'd like to get involved with Lineth, join the #lineth-general on LFDT Discord. Monthly community calls, GitHub issues, and ongoing technical discussions all start there.

→ Repository: github.com/Consensys/linea-monorepo

→ Documentation: docs.linea.build

Contributions are particularly welcome from engineers and researchers working on institutional deployment patterns, prover performance, zkEVM arithmetization, execution-layer extensions, cross-rollup interoperability, and L2 consensus.