JavaScript's Date object has long been a source of bugs due to 0-indexed months, inconsistent parsing, and poor timezone handling. The new Temporal API introduces proper types like PlainDate, PlainDateTime, and ZonedDateTime, mirroring concepts from libraries like NodaTime. This is currently at Stage 3 and requires a polyfill for most browsers.

Beyond the API, the article stresses clear API contracts for time data. It recommends structured objects with `local` and `timeZoneId` fields for user-scheduled events, avoiding ambiguous formats. This ensures the backend receives the user's intent, not a converted UTC timestamp that loses context.

The final piece is DateTimePicker design. Pickers must explicitly collect timezone data when needed and handle Daylight Saving Time gaps and overlaps transparently. The key principle is honesty: the UI display should match what gets stored, preventing silent data corruption. This completes a full-stack approach to handling time correctly.