Lighter is a Layer 2 rollup protocol designed for high-performance decentralised finance (DeFi), offering a verifiable and low-latency trading experience using application-specific zero-knowledge proofs. Its architecture addresses key limitations of general-purpose rollups, including front-running and maximal extractable value (MEV), by implementing fair sequencing, time-priority matching, and zk-SNARK-backed validation. Lighter is built to handle complex order book-based markets, including perpetuals and spot markets, while maintaining trust-minimised guarantees via Ethereum.

Lighter's architecture includes distinct modules for sequencing, proving, data aggregation and exit safety. It enables trustless recovery of funds through its Escape Hatch mechanism, while leveraging data blobs and layered aggregation circuits to compress and verify trading activity efficiently. Designed with extensibility in mind, Lighter also supports programmable multi-step instructions, data compression, and modular applications such as lending and prediction markets.

LIT is the native token of the Lighter protocol. While the protocol focuses heavily on technical and architectural design, the token's utility is expected to support the following roles:

• Fee settlement within the protocol for trades and interactions
• Incentivisation of protocol participants such as sequencers and provers
• Governance over protocol upgrades and parameters
• Collateral or staking in future decentralised roles, such as shared proving or liquidity provisioning

LIT aligns the economic layer with protocol performance, serving as the settlement and coordination asset across trading, verification and network participation.

Lighter introduces a set of interconnected systems optimised for verifiable on-chain trading:

• Sequencer: A low-latency engine that bundles and commits transactions in strict price-time order, while supporting complex order types and market integrations.
• Prover: Generates zero-knowledge proofs for batches of blocks, verifying correctness of matching, state transitions and account updates. Multi-layered aggregation is used to compress proofs efficiently.
• Smart Contracts: Manage user assets, state root commitments, proof verification and censorship-resistant exits.
• Witness Generator: Transforms committed transaction data into public inputs for zk-circuits.
• Escape Hatch: A cryptographic mechanism allowing users to recover assets using only data posted on Ethereum in the event of protocol failure or censorship.

All batches and state changes are published to Ethereum using data blobs. Verification circuits validate every step, from block creation to trade execution.

Lighter supports a programmable instruction stack allowing for multi-step actions, such as:

• Grouped order submission
• Conditional trades
• Linked position adjustments

This design enables composable financial logic, paving the way for lending, collateral flows and structured products to be added modularly.