Fixed Clock

Always returns the same instant, no matter how many times you read it, and never advances — so a setTimeout/setInterval registered against it is never due, regardless of its delay. Built from @time-provider/core/deterministic — see Mental Model.

import { createTimeProvider } from "@time-provider/core/deterministic";
import { plugin } from "@time-provider/plugin-native/deterministic";

const timeProvider = createTimeProvider
  .for(plugin)
  .asFixed()
  .withFixedTime("2026-01-01T00:00:00.000Z")
  .create();

timeProvider.clock.utcNow(); // always 2026-01-01T00:00:00.000Z
timeProvider.clock.utcNow(); // still 2026-01-01T00:00:00.000Z

Use it for tests that assert on a single, deterministic instant and don't need to exercise timers at all — e.g. "the record's createdAt equals clock.utcNow() at creation time." If the code under test schedules timers you actually need to fire, use Manual or Sequential instead.

Fixed Clock ​

Fixed Clock