nautilus-lighter

NautilusTrader adapter for the Lighter decentralized spot and perpetuals exchange.

The nautilus-lighter crate implements the Lighter adapter for NautilusTrader, including typed HTTP and WebSocket clients, REST and stream models, venue parsing, data and execution client wiring, and an in-tree L2 signer for the official Lighter API.

Lighter is a high-throughput central-limit-order-book decentralized crypto exchange for spot and perpetual futures, settling on Ethereum via a custom zero-knowledge rollup. Order matching is performed off-chain by a sequencer, with ZK proofs published on-chain to guarantee correctness of matching, fills, and liquidations.

Trading is non-custodial: users hold their assets in Lighter's smart contracts and authorise trades with their own keys.

NautilusTrader

NautilusTrader is an open-source, production-grade, Rust-native engine for multi-asset, multi-venue trading systems.

The system spans research, deterministic simulation, and live execution within a single event-driven architecture, providing research-to-live semantic parity.

Feature flags

This crate provides feature flags to control source code inclusion during compilation:

python: Enables Python bindings from PyO3.
extension-module: Builds as a Python extension module.

Python bindings are intentionally narrow: configuration, enums, factory wiring, and the integrator revocation helper. Data and execution clients are consumed directly through the Rust trait surface.

High-precision mode (128-bit value types) is enabled by default.

Integrator attribution

Submitted create and modify order transactions carry the NautilusTrader integrator account index in Lighter's L2TxAttributes. This helps us gauge real usage of the integration and prioritize ongoing maintenance. Maker and taker integrator fees are set to zero, so attribution adds no trading cost.

Lighter requires an ApproveIntegrator approval before these attributes can be attached to orders. During startup, the execution client submits the required zero-fee approval for the configured L2 account. See the Lighter integration guide for approval and revocation details.

Maker-only API keys

Lighter restricts maker-only API keys to the 0ms speed-bump lane (PostOnly orders, modifies on ALO orders, and cancels), so they cannot submit ApproveIntegrator themselves. The execution client detects maker-only keys at startup via getMakerOnlyApiKeys and skips the approval with a WARN log. Approval is account-scoped: a single ApproveIntegrator from any non-maker-only key on the same account permanently unlocks orders for every key on that account, including maker-only ones.

L2 transaction signer

The crate ships an in-tree implementation of the Lighter L2 signer (Schnorr over the ECgFp5 curve, Goldilocks field, Poseidon2 binding). Correctness is gated by independent layers:

Vector parity with the upstream Go reference (elliottech/poseidon_crypto) for every algebra layer.
Compiled-signer oracle parity with the signer distributed by the official lighter-python SDK, covering end-to-end outputs for the four supported tx kinds.
Differential parity with Thomas Pornin's MIT-licensed Rust reference (pornin/ecgfp5), kept in the publish=false fuzz crate so the crates.io package graph has no git dependencies. The fuzz targets assert every public algebra operation byte-for-byte against it and soak point decode and scalar multiplication under coverage guidance. Pornin's reference accompanies the curve's design paper (IACR ePrint 2022/274), has been public and reused by downstream zero-knowledge projects since 2022, and shares no code lineage with our implementation: a bug that slips the gate would have to be present in both implementations in the same way.
Property tests covering ring axioms, group laws, and Frobenius identities on the cryptographic primitives.

Round-trip testing against Lighter itself remains the final correctness gate for what the sequencer accepts.

Fuzzing

Coverage-guided fuzz targets for the L2 signer live in fuzz/. They require the workspace-pinned cargo-fuzz binary and a Rust nightly toolchain; install them from the repository root with make install-tools and rustup toolchain install nightly.

Documentation

See the docs for more detailed usage.

License

The source code for NautilusTrader is available on GitHub under the GNU Lesser General Public License v3.0.

Reference attributions for cryptographic parameter sets and reproduced test vectors used by the L2 transaction signer are listed in licenses/THIRD_PARTY_LICENSES.md.

NautilusTrader™ is developed and maintained by Nautech Systems, a technology company specializing in the development of high-performance trading systems. For more information, visit https://nautilustrader.io.

Use of this software is subject to the Disclaimer.