Multi-Factor Stock Ranking and Backtesting in Python — A Practical, Open-Source Framework

Title: Multi-Factor Stock Ranking and Backtesting in Python — A Practical, Open-Source Framework

URL Source: https://medium.com/@amit.943c/multi-factor-stock-ranking-and-backtesting-in-python-a-practical-open-source-framework-7fe0f7d79029?source=rss------python-5

Published Time: 2026-04-17T23:49:36Z

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# Multi-Factor Stock Ranking and Backtesting in Python — A Practical, Open-Source Framework | by Amit Tomar | Apr, 2026 | Medium

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# Multi-Factor Stock Ranking and Backtesting in Python — A Practical, Open-Source Framework

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[Amit Tomar](https://medium.com/@amit.943c?source=post_page---byline--7fe0f7d79029---------------------------------------)

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11 min read

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I built a system that ranks about 100 large-cap U.S. stocks every month using a composite factor score, picks the top 10, equal-weights them, and holds until the next rebalance. It runs on five years of daily data (2020–2025) from Yahoo Finance, benchmarked against SPY.

The backtest came back with a 301% total return and a 1.08 Sharpe. Good numbers on paper. But I spent a fair amount of time after that trying to figure out how much of the result I could actually trust, and the answer was less than I initially thought. A lot of the performance came fro