pit-adjuster

What it is

A zero-dependency Python package that rebuilds daily equity prices onto a fixed back-adjusted basis from current-vintage forward-adjusted bars and a point-in-time corporate-action archive. Each day's price may depend only on events whose ex-date falls on or before that day, and checks ask whether the rebuild inverts the vendor factor chain and still matches raw prices. Researchers working through A-share history, and anyone who must show a historical price was knowable on its date, can run it before a backtest. It does not ship the corporate-action archive or forecast prices, and the caller has to supply and verify event dates, announcement timing, and coverage.