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version: 4.1.0-fractal name: backtesting-frameworks description: Build robust backtesting systems for trading strategies with proper handling of look-ahead bias, survivorship bias, and transaction costs. Use when developing trading algorithms, validating strategies, or building backtesting infrastructure.

Backtesting Frameworks

Build robust, production-grade backtesting systems that avoid common pitfalls and produce reliable strategy performance estimates.

Use this skill when

• Developing trading strategy backtests
• Building backtesting infrastructure
• Validating strategy performance and robustness
• Avoiding common backtesting biases
• Implementing walk-forward analysis

Do not use this skill when

• You need live trading execution or investment advice
• Historical data quality is unknown or incomplete
• The task is only a quick performance summary

Instructions

• Define hypothesis, universe, timeframe, and evaluation criteria.
• Build point-in-time data pipelines and realistic cost models.
• Implement event-driven simulation and execution logic.
• Use train/validation/test splits and walk-forward testing.
• If detailed examples are required, open resources/implementation-playbook.md.

Safety

• Do not present backtests as guarantees of future performance.
• Avoid providing financial or investment advice.

Resources

• resources/implementation-playbook.md for detailed patterns and examples.

🧠 Knowledge Modules (Fractal Skills)

1. implementation-playbook