# Backtesting and Leakage

> Chapter 10 · Reading note · Web version: https://finance-agents.dev/categories/backtesting

Chapter 10 is the market-time layer: point-in-time data, look-ahead control, deterministic replay, and cost models. The chapter question is how an agent loop stays inside the clock.

Full entry list: [Backtesting and Leakage](/chapters/10-backtesting-replay-and-leakage-control). The chapter page ends with a pitfall note.

## What the chapter covers

- Harnesses and engines

## Project pages

- [NautilusTrader](/projects/nautilus-trader)


## Who it is for

For someone checking whether a backtest can see the future, before reading a PnL screenshot.

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GitHub facts: 2026-10-22. CC0 1.0 · https://github.com/aowang-ai/awesome-finance-agents

Maintained by Ao Wang (https://aowang.ai).