Novu

Novu is open-source notification infrastructure that gives developers one API and one system for sending notifications across every channel a product needs, including email, SMS, push, in-app feeds, and chat destinations like Slack, Microsoft Teams, WhatsApp, and Telegram. Instead of wiring up each provider separately and scattering notification logic through a codebase, teams define workflows in Novu with a visual builder, adding steps, channel routing, conditions, delays, and digest logic that batches many events into a single message. Non-technical team members can edit the content and translations of those notifications without a deploy, and Novu ships an embeddable inbox component so a product can add an in-app notification center with a few lines of code. It handles provider failover, subscriber preferences, and delivery tracking, and exposes analytics on what was sent and opened. Novu is available as a fully managed cloud service, self-hosted from its open-source code for teams with data-residency or compliance needs, or a hybrid deployment. The project has a large community and tens of thousands of stars on its public repository. Novu offers a free tier with a monthly event allowance, and paid plans that scale by notification volume and add higher limits, retention, and support.