novuhq/novu

Novu is an open-source notification infrastructure platform that gives developers a single, unified way to send messages across multiple channels, email, SMS, push notifications, in-app inbox alerts, and chat platforms like Slack, without having to wire up each provider separately. Instead of writing separate integrations for SendGrid, Twilio, Firebase, and every other messaging service, you define notification workflows once using Novu's API and it handles routing messages to whichever channel makes sense. The core concept is the notification workflow: you write code that defines a sequence of steps, for example, send an in-app alert first, wait one day to see if the user saw it, then send an email digest if they did not. Each step can have conditions (skip the email if the user is currently online), digest rules (bundle multiple events into one summary), and provider overrides (customize settings per provider). Novu also ships an embeddable React component you can drop into your web app to show users a real-time notification inbox, similar to what you see in apps like GitHub or Notion. Non-technical team members can adjust message templates through a cloud dashboard without touching code. You would reach for Novu when building a web or mobile application that needs to notify users reliably across different channels, things like comment alerts, payment confirmations, task assignments, or onboarding sequences. It saves you from maintaining a tangle of provider-specific integrations. The stack is TypeScript and Node.js throughout, with React components for the frontend inbox widget. It can be self-hosted via Docker or used as a managed cloud service.