Do I need a QuantConnect account to use LEAN CLI?

You can run local backtests without an account using the open-source LEAN engine. A QuantConnect account is needed for cloud features and live trading deployment.

What programming languages does LEAN support?

LEAN supports algorithm development in Python and C#. Both languages have access to the same data and execution APIs.

Can I backtest across multiple asset classes simultaneously?

Yes. LEAN supports multi-asset strategies spanning stocks, options, futures, forex, and crypto within a single algorithm.

LEAN CLI | CLI Trader

TL;DR: LEAN CLI is QuantConnect’s command-line tool for developing, backtesting, and deploying algorithmic trading strategies locally using the open-source LEAN engine.

LEAN CLI provides a local development environment for the QuantConnect LEAN algorithmic trading engine. You can create strategy projects, run backtests against historical data, optimize parameters, and deploy strategies to live trading, all from the terminal. The CLI scaffolds projects with proper structure, manages data downloads, and handles Docker-based execution environments to ensure consistency between local and cloud runs.

The workflow centers on writing algorithms in Python or C#, backtesting them against QuantConnect’s historical data library, analyzing results, and iterating. LEAN CLI supports multiple asset classes including US equities, options, futures, forex, and crypto. It integrates with various brokerages for live deployment including Interactive Brokers, Alpaca, Coinbase, and others. Research notebooks and parameter optimization are also available through the CLI.

LEAN CLI is aimed at quantitative developers and algorithmic traders who want to develop and test strategies locally before deploying them. It assumes familiarity with programming and quantitative concepts. Casual traders looking for simple market monitoring should consider other tools.