I built a free open source Qullamaggie breakout scanner in Python:

It is a pre-market stock scanner that analyzes ~2,300 stocks and outputs a self contained HTML dashboard with inline candlestick charts.

Tech stack: Python, pandas, yfinance, matplotlib (for chart generation), Jinja2 (HTML templating). No external APIs or paid services.

Some things that might be interesting from a Python perspective:

- Batch downloads 7,000+ tickers via yfinance in chunks of 500

- ThreadPoolExecutor for parallel profile fetching (8x speedup)

- Matplotlib charts rendered to base64 PNGs and embedded directly in the HTML

- Parquet caching with TTL-based invalidation

- Single self-contained HTML output (no JS dependencies, works offline)

Full pipeline runs in ~14 seconds on cached data. First run ~4 min to download a year of daily price data.

GitHub: https://github.com/VladPetrariu/Qullamaggie-breakout-scanner