Timestamp Errors in Stock Backtesting: Three Common Pitfalls for Quant Developers

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Quantitative developers building US stock trading strategies often overlook timestamp handling, focusing instead on price and volume data integrity. However, non-standard timestamp processing can introduce three categories of errors across daily, minute-level, and tick-level market data. These bugs tend to be latent, rarely surfacing in early testing but causing significant system failures over time. A recommended best practice is to convert all incoming market data to UTC immediately upon receipt, store it in a unified format, and only convert to US Eastern time for display purposes. Hardcoding fixed timezone offsets is particularly risky, as the UTC-to-Eastern offset shifts with daylight saving time adjustments throughout the year.

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ProgrammingDEV Community ·

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