LN Markets SDK

A Rust SDK for interacting with LN Markets. Supports REST API v3, REST API v2, and WebSocket API.

Note: This is an unofficial SDK. API v3 support is functional but not yet feature-complete. For implementation status, see the API v3 implementation docs.

Repository | Examples | Documentation

Getting Started

Rust Version

This project's MSRV is 1.88.

Dependencies

[dependencies]
lnm-sdk = "<lnm-sdk-version>"

Usage

This SDK provides strong type-safety with validated types for all parameters used in trade operations. All necessary models can be imported via the models mod of the API version in question.

// When working with API v3
use lnm_sdk::api_v3::{RestClient, RestClientConfig, models::*, error::*};

// When working with API v2
use lnm_sdk::api_v2::{
    RestClient, RestClientConfig, WebSocketChannel, WebSocketClient, WebSocketClientConfig,
    WebSocketUpdate, error::*, models::*,
};

Examples

Complete runnable examples are available in the lnm-sdk/examples directory.

REST API v3 - Public

use lnm_sdk::api_v3::{RestClient, RestClientConfig};

//...

let domain = env::var("LNM_API_DOMAIN").expect("LNM_API_DOMAIN must be set");

let rest = RestClient::new(RestClientConfig::default(), &domain)?;
    
// Get the futures ticker
let _ticker = rest.futures_data.get_ticker().await?;

// Get candles (OHLCs) history
let _candles = rest
    .futures_data
    .get_candles(None, None, None, None, None)
    .await?;

For more complete public API examples, see the v3_rest_public example.

REST API v3 - Authenticated

use lnm_sdk::api_v3::{
    RestClient, RestClientConfig,
    models::{Leverage, Quantity, TradeExecution, TradeSide, TradeSize},
};

// ...

let domain = env::var("LNM_API_DOMAIN").expect("LNM_API_DOMAIN must be set");
let key = env::var("LNM_API_V3_KEY").expect("LNM_API_V3_KEY must be set");
let secret = env::var("LNM_API_V3_SECRET").expect("LNM_API_V3_SECRET must be set");
let passphrase = env::var("LNM_API_V3_PASSPHRASE").expect("LNM_API_V3_PASSPHRASE must be set");

let rest = RestClient::with_credentials(
    RestClientConfig::default(),
    &domain,
    key,
    secret,
    passphrase,
)?;
    
// Get account information
let _account = rest.account.get_account().await?;

// Place a new isolated trade
let trade = rest
    .futures_isolated
    .new_trade(
        TradeSide::Buy,
        TradeSize::from(Quantity::try_from(1)?), // 1 USD
        Leverage::try_from(30)?,                 // 30x leverage
        TradeExecution::Market,
        None, // stoploss
        None, // takeprofit
        None, // client trade id
    )
    .await?;

// Close the trade
let _closed_trade = rest
    .futures_isolated
    .close_trade(trade.id())
    .await?;
  
// Place a new cross order
let _new_order = rest
    .futures_cross
    .place_order(
        TradeSide::Buy,
        Quantity::try_from(1)?, // 1 USD
        TradeExecution::Market,
        None, // client order id
    )
    .await?;

let _close_order = rest.futures_cross.close_position().await?;

For more complete authenticated REST API examples, see the v3_rest_auth example.

WebSocket API

The SDK implements the WebSocket API for real-time market data streaming using fastwebsockets.

Key Features:

• Real-time Data Streaming: Persistent WebSocket connection with broadcast channels for concurrent consumers
• Connection Reliability:
  • Automatic heartbeat monitoring (5-second intervals)
  • Ping/Pong frame handling
  • Graceful disconnection with configurable timeout
  • TLS/SSL encryption via tokio-rustls
• Subscription Management:
  • Prevents conflicting operations on the same channel
  • State tracking for subscribe/unsubscribe requests with server confirmation

use lnm_sdk::api_v2::{WebSocketChannel, WebSocketClient, WebSocketClientConfig, WebSocketUpdate};

// ...

let domain = env::var("LNM_API_DOMAIN").expect("LNM_API_DOMAIN must be set");

let client = WebSocketClient::new(WebSocketClientConfig::default(), domain);

let ws = client.connect().await?;
let mut ws_rx = ws.receiver().await?;

ws.subscribe(vec![
    WebSocketChannel::FuturesBtcUsdIndex,
    WebSocketChannel::FuturesBtcUsdLastPrice,
])
.await?;

while let Ok(ws_update) = ws_rx.recv().await {
    match ws_update {
        WebSocketUpdate::ConnectionStatus(status) => {
            println!("{status}");
        }
        WebSocketUpdate::PriceTick(price_tick) => {
            println!("{price_tick}");
        }
        WebSocketUpdate::PriceIndex(price_index) => {
            println!("{price_index}");
        }
    }
}

For a more complete WebSocket API example, see the v2_ws example.

Testing

Some tests require environment variables and are ignored by default. Moreover, said tests must be run sequentially as they depend on exchange state. The full test suite can be executed by setting the LNM_API_* variables or adding a .env file to the project root (a .env.template file is available), and then running:

cargo test -- --include-ignored --test-threads=1

API Reference

• LN Markets API v3 Documentation (recommended)
• LN Markets API v2 Documentation (REST API v2 is deprecated)

Development History

This crate was originally developed as part of the quantoxide repository before being extracted into a standalone repository on 2025-12-26 at quantoxide commit 0d78ee08. The full development history was preserved.

License

This project is licensed under the Apache License (Version 2.0).

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion by you, shall be licensed as Apache-2.0, without any additional terms or conditions.