Lighter lit

Lighter is a decentralized trading platform and Ethereum-anchored, application-specific ZK rollup focused on order-book trading. Its design targets perpetual futures and spot markets with low latency, high throughput, and zero fees for standard retail accounts. The project describes itself as a fully verifiable exchange: order matching, liquidations, and state transitions are backed by custom zero-knowledge proofs rather than relying only on an operator's promise.

Lighter Core combines a custom exchange proving engine with Ethereum as the settlement and security anchor. Deposited assets and the canonical state root are held/recorded through Ethereum smart contracts, and state updates are accepted only after proof verification. The state root covers user balances and positions, public pools, order books, and other critical exchange state.

The ecosystem token is LIT (Lighter Infrastructure Token). Official documentation assigns LIT staking utility to access the Lighter Liquidity Pool (LLP), staking rewards, and fee discounts for opt-in Premium accounts. The protocol also documents buybacks funded by trading-fee revenue.

Users access the exchange at app.lighter.xyz; official docs and the project site provide the architecture, trading, security, and token-utility material.

Conventional centralized exchanges provide fast order-book execution but require users to trust the operator for fair matching, liquidation correctness, custody, and continued access. Fully decentralized on-chain order books, by contrast, can incur consensus latency, limited throughput, and high execution costs. Lighter's stated objective is to combine exchange-grade performance with cryptographically verifiable execution and Ethereum-backed exits.

The project specifically addresses the inability to independently verify off-chain matching and liquidation engines. Lighter says its matching engine uses SNARKs to prove price-time priority and its execution pipeline proves batches of deterministic, user-signed transactions. It also addresses operator liveness/censorship risk through an Ethereum priority-request queue and an Escape Hatch: if the sequencer misses required processing deadlines, the contract freezes and users can reconstruct state from Ethereum-posted data to withdraw directly.

These guarantees do not remove trading risks: perpetuals use leverage, funding and liquidation; market orders can slip; and users remain exposed to smart-contract, proof-system, oracle/mark-price, liquidity, and operational risks.

Users connect an Ethereum wallet, register an account, and deposit assets into Lighter's smart contracts. Exchange operations are represented as user-signed transactions. A sequencer orders them FIFO and provides soft finality, while API services distribute low-latency data to users.

The matching and risk engines execute transactions deterministically. Lighter supports market and limit orders, post-only, reduce-only, IOC and GTT instructions, stop-loss/take-profit, TWAP, advanced TWAP, chase-limit, and atomic basket orders. Matching follows price-time priority: best price first and oldest order first at an equal price; the taker executes at the maker's price.

Witness generators transform execution data into circuit-friendly inputs. The prover generates many execution proofs in parallel, then a multi-layer aggregation engine combines them into a succinct batch proof. Ethereum contracts verify the proof and update the canonical Lighter state root; compressed data blobs allow users to reconstruct account state independently.

For liveness, users may submit priority exits, public-pool exits, or reduce-only IOC orders directly on Ethereum. If the sequencer fails its deadline, Escape Hatch mode freezes the core contract and users can generate ownership proofs from Ethereum data to withdraw balances, positions, or pool shares without off-chain coordination.