---
id: waiting
version: "1.5.0"
license: BSD 3-Clause License
license_treatment: permissive
maintenance: dormant
---

# waiting — Utility for waiting for stuff to happen

License: permissive · Maintenance: dormant · Downloads: 612.7K/mo

## What it is and what it does

Waiting is a small polling utility that repeatedly calls a predicate function until it returns True, handling timeouts and sleep intervals. It's designed for scenarios where you need to wait for a condition to be satisfied—such as a resource becoming available, a service becoming ready, or a background task completing—without blocking or busy-waiting.

The library supports flexible polling strategies: fixed sleep intervals, exponential backoff with configurable growth rates, and aggregation of multiple predicates using ANY and ALL constructs. It can suppress specific exceptions during polling, invoke a callback after each poll cycle, and provide descriptive timeout messages. With no runtime dependencies and pure-Python implementation, it integrates easily into test suites, integration code, and operational scripts.

Use it for:

- Test fixtures that wait for a service to become ready before running test cases.
- Integration code that polls an API or resource until a desired state is reached, with exponential backoff to reduce load.
- Operational scripts that wait for multiple conditions to be satisfied before proceeding (using ANY or ALL aggregators).
- Retry logic that waits for transient failures to resolve, ignoring expected exceptions during polling.
- Monitoring or health-check loops that periodically verify a condition and log progress via on_poll callbacks.

## Worth the install?

AI-flagged interpretation of the facts above — verify before relying.

Waiting is a lightweight library for polling a predicate function until it returns True, with support for timeouts, custom sleep intervals, exponential backoff, and aggregation of multiple predicates.

Yes. Waiting is a stable, lightweight utility with no dependencies, permissive licensing, and a clear use case in testing and operational code. The dormant maintenance status is not a concern for a mature, focused library with no known vulnerabilities. Install it if you need straightforward predicate polling with timeout and backoff support.

## Install

pip install waiting
uv add waiting
poetry add waiting

## Installing waiting

Before you install: Low friction: pure Python wheel with no runtime dependencies. Dormant maintenance status (716 days since last release), but the package is stable and has been in use since 2011.

License in practice: BSD 3-Clause License is permissive; you may use, modify, and distribute this package freely in commercial and private projects with minimal restrictions.

Quickstart:

from waiting import wait, TimeoutExpired

predicate = lambda: True
result = wait(predicate, timeout_seconds=10)

# With exponential backoff
result = wait(predicate, sleep_seconds=(1, 100))

# Catch timeout
try:
    wait(lambda: False, timeout_seconds=5, waiting_for="something")
except TimeoutExpired:
    pass

Requires Python 3.8 or later.

Verify before relying:

- Whether the package works correctly with flux for simulated timelines (mentioned in description but not detailed).
- Performance characteristics when polling very frequently or with many predicates aggregated via ANY/ALL.

## Package facts

- License: BSD 3-Clause License (permissive)
- Python support: supports_current
- Install friction: low
- Maintenance: dormant
- Downloads: 612.7K/month (top 15,000 on PyPI)
- Known vulnerabilities: none known

## Tags

polling predicate function, wait for condition to be true, timeout polling library, exponential backoff retry, wait until predicate satisfied, polling with timeout, condition polling utility, polling, testing-utility, retry-logic

[View on SkillFed](https://skillfed.io/packages/waiting) · [View on PyPI](https://pypi.org/project/waiting/)