Why This Matters If a backtest seems to “forecast” the future without any explanatory edge, it probably does. The culprit is usually look‑ahead bias: using information you could not have known at the time of the decision. Below are the most common categories, each with a tiny example and a safe...
Source: [Dev.to](https://dev.to/joor0x/look-ahead-traps-in-backtesting-backtrader-mql-pinescript-33cn)