The Hard Part of a Global Birth-Chart Calculator Was Time

A birth-chart form looks simple: ask for a date, time, and place, then calculate.

The interface may be simple. The input is not.

1992-11-01 01:30 does not identify one universal instant. It is a wall-clock reading that only becomes meaningful after you resolve the place, the historical time-zone rule, and any daylight-saving transition. If the time is unknown, inventing a convenient default can create chart features that were never supported by the user’s data.

I ran into these problems while building , or try the free calculated chart. No email is required for the free calculation.

I would be especially interested in how other developers handle DST folds, historical time-zone data, and WASM assets in serverless deployments.

Scope note: BaZi and astrology are traditional symbolic systems used for reflection and entertainment. They are not scientifically validated diagnostic or predictive methods. Better engineering can make a calculation pipeline more consistent and transparent; it does not establish the scientific validity of the interpretation.