Scheduled functions

Firenook runs your scheduled functions on time, as Cloud Scheduler does in production. This page explains when they run, how to run one now, how to pause one, and how time zones work.

Schedules run on their own

The official emulator never runs a schedule by itself: a scheduled function runs there only when you trigger it. In Firenook, a function that runs every minute does run every minute, and writes what it writes. Pause it while you work if you don’t want that.

A scheduled function

functions/index.js

const {onSchedule} = require("firebase-functions/scheduler");
const logger = require("firebase-functions/logger");

exports.nightlyReport = onSchedule(
  {schedule: "every day 02:30", timeZone: "Europe/Paris"},
  async () => {
    logger.info("nightly report ran");
  },
);

exports.cleanup = onSchedule("every 1 minutes", async () => {
  logger.info("cleanup ran");
});

How Firenook runs a schedule

Each scheduled function gets a Pub/Sub topic named firebase-schedule-<function>, as in the official emulator. On every tick, Firenook’s scheduler publishes a message to that topic, and the function runs. The start-up screen counts the schedules on the Pub/Sub row:

  Functions   ✓ 213 ms  2 functions
  Pub/Sub     ✓   1 ms  2 schedules

So schedules run only while the Pub/Sub emulator runs. Your firebase.json needs an emulators.pubsub entry, and if you start with --only, the list must include pubsub. Without Pub/Sub nothing runs on time, but you can still run each function by hand.

A schedule’s clock starts when its function loads:

• every 5 minutes runs five minutes after the start, then every five minutes.
• A clock time, such as every day 02:30, runs at the next 02:30 in the schedule’s time zone.
• A reload keeps an unchanged schedule’s next run. A changed schedule starts its clock again.
• Runs that fall while Firenook is stopped are not made up. If your computer sleeps through several runs, the schedule runs once when it wakes, then carries on.

Each run is a line in the terminal’s log, like any other call:

     19:39:46    ✓ cleanup          12 ms  schedule · scheduled tick
                 │ cleanup ran

Schedule expressions

Firenook reads the expressions Cloud Scheduler takes for Firebase:

Form	Examples
Every N minutes or hours	every 5 minutes, every 15 mins, every 2 hours
Every N minutes or hours within a daily window	every 2 hours from 10:00 to 14:00
Aligned to midnight	every 15 mins synchronized
Every day at a time	every day 02:30
Given weekdays at a time	every monday 09:00, every mon,wed,fri 09:00
Cron, five fields	0 9 * * 1-5

When Firenook cannot run an expression on a clock, the function still loads, and you can still run it by hand. The plain log (--plain, or any pipe) says why:

firenook pubsub: schedule of us-central1-fastPoll not run automatically (unsupported Firebase schedule expression: every 30 seconds); run it from the console or through the Functions trigger route

In a terminal, it is one of the start-up warnings: the ready summary says 1 start-up warning · press w to show it, and w shows it in the log:

     19:38:33    ! schedule of us-central1-fastPoll not run automatically (unsupported Firebase schedule
                   expression: every 30 seconds); run it from the console or through the Functions trigger
                   route

The console marks such a schedule Not automatic.

Run one now

From the command line, while the emulators run:

$ npx firenook functions:invoke nightlyReport --event-data '{}'
Firenook: schedule event pubsub for nightlyReport (us-central1, gcfv2) via trigger key us-central1-nightlyReport-0
200 OK http://127.0.0.1:5001/functions/projects/demo-shop/triggers/us-central1-nightlyReport-0

A schedule takes no data, so --event-data '{}' is enough. In 0.2.0 it is also needed: without it, functions:invoke sends a plain HTTPS request, which a scheduled function does not answer, and the command exits with 1:

$ npx firenook functions:invoke nightlyReport
404 Not Found http://127.0.0.1:5001/demo-shop/us-central1/nightlyReport
Function us-central1-nightlyReport does not exist, valid functions are: us-central1-helloWorld, us-central1-addMessage, us-central1-onOrderCreated-0, us-central1-onUpload-0, us-central1-nightlyReport-0, us-central1-sendReceipt, us-central1-onShipped-0-projects/demo-shop/locations/us-central1/channels/firebase

In the console, open Functions and pick the function. Its Schedule tab shows the expression, the zone it runs in, the next five runs and the recent ones, with Run now, Pause and Resume. Run now sends the same tick as the clock, and works without Pub/Sub too. The list of functions shows each schedule’s next run.

A coding agent has the same controls in the schedules_list and schedules_run MCP tools.

Publishing a message to the function’s topic, firebase-schedule-<function>, also runs it, as it does in the official emulator. The terminal has no key that runs a schedule.

Pause a schedule

Pause on the Schedule tab stops a schedule’s clock until you press Resume. Run now still works while it is paused. A pause lasts until Firenook stops: every start begins with every schedule running.

Time zones

Clock times and cron fields are read in the schedule’s timeZone. Firenook carries its own copy of the IANA time-zone database, so Europe/Paris runs at the same moments on every machine, including containers that have no /usr/share/zoneinfo.

Daylight saving follows the zone. A time the change skips runs right after the gap, and a time it repeats runs once, the first time. For every day 02:30 in Europe/Paris, the next runs Firenook lists in UTC move by an hour when summer time ends on 25 October 2026:

2026-10-24T00:30:00.000Z
2026-10-25T00:30:00.000Z
2026-10-26T01:30:00.000Z

Without timeZone, Firenook uses UTC. That is the production default for onSchedule. A first-generation functions.pubsub.schedule() without .timeZone() runs in America/Los_Angeles in production, but in UTC in Firenook, so name the zone when the hour matters.

A zone that is not in the database stops the schedule from running on its own:

firenook pubsub: schedule of us-central1-marsReport not run automatically (time zone Mars/Olympus is not in this engine's time-zone database); run it from the console or through the Functions trigger route

Your function’s code runs with TZ=UTC, so new Date().getHours() gives the UTC hour whatever zone the schedule is in.

Next

Give your functions their settings with environment variables and secrets, or see how Pub/Sub delivers the ticks.