Tim Düsterhus and Derick Rethans have proposed a new `Time\Duration` class for PHP 8.6, designed to represent stopwatch-style durations for timeout APIs. The RFC is intentionally minimal, using a seconds + nanoseconds internal representation (similar to Rust's and Java's Duration). Key design decisions discussed include: the highest constructor unit being hours, ISO-8601 period string parsing (PT-prefixed strings only), omission of floating-point conversion methods to avoid precision/rounding issues, and use of the `Time` namespace rather than `DateTime`. Community feedback raised questions about ISO 8601 serialization, float total methods, namespace choice, and whether to use `add`/`sub` methods vs. a variadic `sum` method. The RFC is positioned as the first step toward a modernized PHP date/time API, following the pattern of new namespaced APIs introduced in PHP 8.2–8.5.
