Import
import { DateTimes } from "@typed/id/DateTimes";Signatures
export declare class DateTimes extends DateTimes_base {
static readonly now: Effect.Effect<number, never, DateTimes>;
static readonly date: Effect.Effect<Date, never, DateTimes>;
static readonly Default: Layer.Layer<DateTimes, never, never>;
static readonly Fixed: (baseDate: number | string | Date) => Layer.Layer<DateTimes, Cause.IllegalArgumentError, never>;
}Why
Making time a service keeps time-based ID generators deterministic under tests and explicit under server or browser runtimes.
Ownership and lifetime
A DateTimes Layer owns its time source for the Layer lifetime; individual reads acquire no resources.
Property: Default
Provides DateTimes using the runtime wall clock.
Property: Default: Why
The production default is explicit and replaceable rather than hidden in each generator.
Property: Default: Ownership and lifetime
The surrounding Layer Scope owns the service; reads allocate only their returned Date values.
Property: Fixed
Provides DateTimes anchored to a base date and advanced by Effect Clock.
Property: Fixed: Why
Clock-relative time supports deterministic tests while still allowing controlled advancement; invalid bases fail with IllegalArgumentError.
Property: Fixed: Ownership and lifetime
Layer acquisition captures the base and current Clock reading; the surrounding Layer Scope owns that state.
Property: date
Reads a Date from the current DateTimes service.
Property: date: Why
The Date view stays aligned with the same replaceable time source as epoch-millisecond reads.
Property: date: Ownership and lifetime
This Effect acquires no resources and uses the DateTimes service for one invocation.
Property: now
Reads epoch milliseconds from the current DateTimes service.
Property: now: Why
A service-backed read avoids hard-wiring Date.now into generators and tests.
Property: now: Ownership and lifetime
This Effect acquires no resources and uses the DateTimes service for one invocation.
Examples
import { DateTimes } from "@typed/id/DateTimes"
import { Effect } from "effect"
const now = Effect.provide(DateTimes.now, DateTimes.Default)See Effect Clock.
import { DateTimes } from "@typed/id/DateTimes"
const fixed = DateTimes.Fixed("2026-01-01T00:00:00Z")Other public imports
These import paths expose the same declaration. Each page retains its own public name and signature.