Welcome to RustMailer Docs

Rustmailer is a fully asynchronous, high-performance email service middleware written in Rust. it handles thousands of concurrent operations effortlessly through non-blocking I/O and efficient task scheduling.

Supports both gRPC and RESTful OpenAPI interfaces, with built-in support for Swagger UI, Redoc, Scalar, and OpenAPI Explorer.

Full OAuth2 support with automatic token refresh, making it easy to integrate with various email providers like Gmail, Outlook, and others.

Customizable event hooks with VRL (Vector Remap Language) support for payload transformation and filtering to adapt to different receiving systems.

Supports all IMAP operations including email search, folder management, message retrieval, and more - all available through a clean API.

Handlebars-powered email templating system with support for dynamic content and personalization.

Real-time notifications for email events including opens, link clicks, new arrivals, delivery status (success/bounce), and flag changes. Delivered via Webhooks/NATS.

Exposes key metrics via Prometheus: traffic volume, delivery success rates, API request counts, and latency distributions. Provides raw metrics without built-in analytics.

Queue and schedule emails through your existing SMTP/MTA infrastructure with delivery timing and automatic retries.

No external dependencies - uses embedded databases and runs as a standalone service without requiring Redis, MySQL, or PostgreSQL.

Built-in web UI for administration and a web-based email client for easy viewing and debugging.

Supports event publishing via both HTTP webhooks and NATS messaging for scalable event-driven architectures.