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Temporal API
The Temporal API is the modern replacement for the legacy Date object in JavaScript. It provides immutable date/time types, proper time zone support, calendar systems, and nanosecond precision.
Temporal has reached Stage 4 in TC39 and is already shipping in Chrome/Edge and Firefox. Safari/WebKit still lacks full support (or has incomplete support). This creates a significant interoperability gap for a fundamental language feature that developers have been waiting for for many years.
Because Temporal is designed as a full replacement for Date, incomplete support forces developers to either:
- Continue using the broken
DateAPI - Ship large polyfills
- Use feature detection + dual code paths
Making Temporal fully interoperable across all major engines would remove one of the longest-standing pain points in the JavaScript language.
Discussion on GitHub (3)
Are there more tests than https://wpt.fyi/results/third_party/test262/test/intl402/Temporal?label=experimental&label=master&aligned? Those look like they have very high pass rates in all prerelease browsers.
Supporting this proposal.
In production transactional and real-time applications, date and time handling quickly goes beyond formatting a timestamp for the UI. Event ordering, transaction history, recovery flows, reporting, and converting between system time and local time all depend on having predictable time semantics.
The current interoperability gap also creates an awkward adoption problem: even when Temporal is the better model, teams targeting all major browsers still need a polyfill or a second path around Date.
Getting Temporal consistently available across engines would make it much easier to treat it as the platform default rather than an optional dependency.
Searching more generically, https://wpt.fyi/results/third_party/test262/test?label=master&label=experimental&aligned&q=temporal finds a load more — but still very high pass rates in all prerelease browsers.