Qelv

An independent trader. March 2024 to May 2026.

Market-data tooling for a trader, on a two-year retainer

A trader had alerts in one format, market history in another and no way to ask what a price was when an alert fired. Five Python modules enrich the alerts from Polygon, normalise the timestamps and prepare his backtest datasets, on a retainer from March 2024 to May 2026.

Financial markets. Data.

Market-data backtesting in figures

  • 26 monthson retainer, March 2024 to May 2026
  • 5Python modules, from alert enrichment to backtest datasets
  • Trade alerts
  • Polygon market history
  • Timestamp normalisation
  • Price at a given time
  • Backtest datasets
The parts of the system.

Screens from this system are being added.

The situation

An independent trader had alerts in one format, market history in another and no dependable way to ask what a price was at the moment an alert fired. Every backtest started with the same data wrangling, done by hand.

What we built

  • A module that enriches trade alerts with historical bars from the Polygon API
  • Timestamp normalisation across the alert feed and the market data, so the two line up to the minute
  • Price lookup at a given time, including the edge cases around market open and close
  • Dataset preparation for analysis, written so each backtest starts from the same clean table
  • Walkthroughs of the code with the trader as the tooling grew, over two years of retained work

What changed

The trader spends his time on the strategy, not on the data underneath it, and kept the retainer running for 26 months.

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Where to next

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