QuantConnect LEAN
Some data may be outdated — see provenance labels.
Lean Algorithmic Trading Engine by QuantConnect (Python, C#) observed · 2026-09-26
Health v2 · maintenance only
66/100
- Activity 96
- Release rhythm 8
- Longevity 100
How is this computed?
round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10) — computed 2026-10-21. Adoption (stars, forks) is never an input.
- gap_med: n/a
- age_days: 4344
- days_rel: n/a
- days_push: 25
- n_releases_24m: 0
Adoption not part of the score
21779 stars · 5261 forks observed · 2026-09-26
What it is AI-extracted, prompt v1, taxonomy v1, 2026-10-19, confidence 0.97
LEAN is an open‑source, event‑driven algorithmic trading engine written in C# with Python support. It provides a modular framework for research, backtesting, optimization, and live trading across many brokerages.
Use cases
- backtest trading strategies on historical market data
- run live algorithmic trading with broker integration
- develop quantitative finance models in Python or C#
- optimize portfolio allocations using built‑in analytics
- simulate order execution, slippage and fees
- import and process alternative data sources for strategies
When to choose
- you need a fully open‑source platform that supports both Python and C#
- you want a modular architecture with pluggable components and many broker integrations
- you require built‑in backtesting, optimization and live‑trading capabilities
- you prefer a community‑driven project with active development and extensive documentation
When to avoid
- ultra‑low‑latency high‑frequency trading where nanosecond performance is critical
- you prefer a fully managed SaaS solution with no infrastructure overhead
- your team works exclusively in languages other than Python or .NET
- you need a turnkey desktop GUI without command‑line interaction
Facets
framework · maturity active
api-framework cli data-science analytics python dotnet windows cloud cross-platform algorithmic-trading quant backtesting live-trading modular csharp python brokerage-integration linux macos docker
7 sources
- readme: https://github.com/QuantConnect/Lean · fetched 2026-09-26 · 74c4d256c208
- homepage: https://lean.io · fetched 2026-10-05 · b1a049b71022
- site_page: https://www.lean.io/docs/v2/lean-cli · fetched 2026-10-05 · ec525dba35dd
- site_page: https://www.lean.io/docs/v2/lean-cli/key-concepts/getting-started · fetched 2026-10-05 · 85bfe86218dc
- site_page: https://www.lean.io/docs · fetched 2026-10-05 · 73d80ea63b46
- site_page: https://www.lean.io/about · fetched 2026-10-05 · 2273e219ddc8
- site_page: https://www.lean.io/pricing · fetched 2026-10-05 · 2273e219ddc8
Member repositories
| Repository | Role | Health v2 |
|---|---|---|
| QuantConnect/Lean | main | 66 |
| QuantConnect/Tutorials | examples | 44 |
| QuantConnect/lean-cli | backend | 94 |
| QuantConnect/Documentation | docs | 75 |
| QuantConnect/IBAutomater | plugin | 72 |
| QuantConnect/Lean.Brokerages.InteractiveBrokers | plugin | 75 |
For agents
markdown · JSON · MCP: product_card(name="QuantConnect/Lean")
Data as of 2026-10-19T08:05:51.212177+00:00 · Report a problem