Knock

Knock is a customer engagement infrastructure designed for product-led growth, allowing businesses to send product, marketing, and transactional messaging across various channels. It provides developer-first tooling to build custom messaging experiences without compromising design, performance, or user experience, supporting channels like email, SMS, push, chat, and in-app notifications. The platform features an intuitive drag-and-drop editor for building messaging journeys and ensures on-brand, error-free communication with global styles, reusable blocks, and live previews. The platform unifies and activates real-time data from product and warehouse sources, enabling relevant and timely messaging triggered by user attributes, events, or actions. It supports data ingestion from CDPs and reverse ETL, dynamic segmentation, and personalized messaging with conditional logic. Knock is built for developers, offering SDKs in major languages, a CLI, environments, version control, and CI/CD integration, making it suitable for integrating into existing development workflows and AI-powered IDEs. It also offers robust infrastructure with high uptime, scaled delivery, and compliance certifications like HIPAA, SOC2, GDPR, and CCPA.