3 Open Source Alternatives to Customer.io

A list of 3 carefully selected open-source alternatives to Customer.io.

Created by

Adrian

Mar 9, 2025Updated•4 min read

The open-source alternatives are ranked based on our custom ranking system and score. This system takes into account various factors to determine the best alternatives.

If you’re looking for alternative features or workflows, here is a prepared detailed list of Customer.io open-source alternatives — each with its own distinctive strengths and key features.

Novu

36,378

3,972

Novu is an open-source notification platform that streamlines multi-channel delivery into a single embeddable Inbox component. It empowers developers and product teams to integrate in-app, email, push, SMS, chat, and custom notifications with just a few lines of code.

Key Features

Embeddable Inbox component with user preference management
Multi-channel support: in-app, email, push, SMS, chat, and custom channels
Unified API for streamlined workflow orchestration
Real-time notification delivery with minimal coding
Block-based email editor for dynamic, customizable emails
Robust security features including token management

Novu transforms complex multi-channel notification delivery into an easy-to-integrate solution. Built for modern development, it offers a unified API for managing workflows, real-time notifications, email digesting, and a block-based email editor. Its flexible design supports various frameworks like Next.js, Remix, and React, ensuring that you can start simple and scale as your needs evolve.

Learn more about Novu

Pushify

Pushify is an open source push notifications service designed to send messages directly to your phone via a simple REST API. It seamlessly integrates with any application, including SaaS platforms, eliminating the need to develop a dedicated mobile app.

Key Features

Simple HTTP-based REST API for push notifications
Supports multiple programming languages (Node.js, Python, Java)
Easy integration with any application or SaaS platform
Open source code available for review and contribution
Free for 1 device and up to 2500 push notifications per month during Beta

Pushify offers a straightforward HTTP-based API that enables developers to send push notifications with minimal effort. Built with simplicity in mind, it supports multiple programming languages such as Node.js, Python, and Java, and its open source nature encourages collaboration and customization. It is ideal for individual developers and SaaS platforms aiming to provide real-time communication to their users.

Learn more about Pushify

Unsend

800

Unsend is an open source alternative to traditional email services like Resend, Sendgrid, and Postmark. It streamlines sending transactional, marketing emails, SMS, and push notifications, making communication effortless for developers.

Key Features

Effortless setup for transactional emails
Reliable inbox delivery with bounce and complaint notifications
No-code email builder with versatile templates
Click and open tracking for actionable engagement insights
Supports SMS and push notifications alongside emails

Unsend provides a robust sending infrastructure that enables developers to integrate email, SMS, and push notification functionalities in minutes. It features a straightforward API, simple configuration, and practical code examples for various programming languages, ensuring your messages reach the inbox, not the spam folder.

Learn more about Unsend

Price comparison of Customer.io open-source alternatives

Tool	Tier 1	Tier 2	Tier 3	Details
Novu	$0 Free	$30 Pro	$250 Team	Learn more
Pushify	$0 Beta Pricing	-	-	Learn more

* Pricing shown is based on publicly available information and may not reflect current rates. Visit each tool's website for detailed pricing information and additional tiers.

About Customer.io

Customer.io is a leading brand that helps businesses around the world strengthen their relationships with customers through automated messaging campaigns. Thousands of companies across various industries trust and rely on Customer.io to send personalized marketing messages and improve customer engagement. With Customer.io, businesses can easily automate their marketing messages, collect and route data to different tools, and sync data with popular platforms like Snowflake and BigQuery. The brand also offers features such as in-app messages, audience syncing with Google and Facebook Ads, identity resolution, and a visual workflow builder for creating campaigns. Customer.io provides scalability, making it suitable for businesses with over 100 million customers. The platform also focuses on data and security compliance, ensuring the protection of customer information. In addition to its powerful features, Customer.io offers extensive resources such as documentation, API resources, webinars, and guides to help businesses make the most of their platform. The brand takes pride in its customer success and has been highly recommended by companies in various industries for its flexibility, ease of use, and exceptional customer support. With Customer.io, businesses can enhance their messaging strategies, drive customer engagement, and achieve their marketing goals effectively.

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