PHP internals discussion thread covering a proposed RFC to introduce a new `Time\Duration` class in PHP 8.6. The class is designed to represent stopwatch-style durations (not calendar periods) with nanosecond precision, stored internally as a seconds+nanoseconds pair. It targets the new Polling API already in PHP 8.6 and is intended as the first step toward a modernized date/time API. The thread covers design decisions including: why the highest constructor unit is hours while internal representation uses seconds; why ISO 8601 serialization is omitted for now; why floating-point total methods were deferred due to precision concerns; namespace choice (`Time` vs `DateTime`); and whether to use `add`/`sub` methods or a single variadic `sum` method. The authors explicitly modeled the design after Java's `java.time` and Rust's `std::time::Duration`, and rejected using the `temporal_rs` Rust library as an implementation backend.
