useSend is an open-source email delivery platform designed as a self-hostable alternative to commercial services like Resend, SendGrid, and Postmark. Built on top of Amazon SES, it provides a full-featured dashboard for sending transactional and marketing emails while giving users complete control over their email infrastructure. It’s ideal for developers, DevOps teams, and startups seeking to reduce costs and avoid vendor lock-in while maintaining reliability and visibility into email delivery metrics. The project is currently in beta and actively seeking community feedback for its first production release.
useSend supports SMTP, REST APIs, scheduled sending, domain management, and real-time analytics for opens, clicks, bounces, and deliveries. With Docker and one-click Railway deployment options, it’s designed for easy self-hosting on any infrastructure. The frontend is built with Next.js, tRPC, and shadcn/ui, while the backend uses Prisma for data modeling and Redis for queuing. It’s AGPLv3 licensed, ensuring the software remains free and open for all users.
What You Get
- Transactional Emails - Send personalized, on-demand emails (e.g., password resets, notifications) via REST API or SMTP with full delivery tracking.
- Marketing Emails (Newsletters) - Create and schedule bulk email campaigns to subscriber lists with built-in subscription management.
- Email Dashboard - Real-time analytics showing delivered, opened, clicked, and bounced emails with visual metrics for performance monitoring.
- SMTP Support - Use standard SMTP protocols to integrate useSend with existing applications, CMS platforms, or legacy systems without code changes.
- Scheduled API - Schedule email delivery for future timestamps via the REST API, useful for time-sensitive campaigns or reminders.
- Domain Management - Add and verify custom domains to send emails with your brand’s domain, improving deliverability and trust.
- Docker & Railway Deployment - Deploy useSend in minutes using pre-built Docker images or one-click deployment on Railway with automatic environment configuration.
Common Use Cases
- Building a SaaS product with email notifications - Developers building applications that require transactional emails (like account verification or password resets) can self-host useSend to avoid per-email costs and gain full control over delivery logs.
- Running a newsletter platform with 10k+ subscribers - Marketing teams can use useSend’s bulk sending and analytics to manage email campaigns without relying on third-party platforms like Mailchimp or SendGrid.
- Problem: High email service costs → Solution: useSend - Companies paying $0.10+ per email on SendGrid or Resend can reduce costs by 90% by self-hosting useSend with Amazon SES, while retaining a modern dashboard and API.
- DevOps teams managing multi-environment email delivery - Teams deploying across staging, production, and CI/CD pipelines can use useSend’s containerized setup to ensure consistent email behavior across environments.
Under The Hood
Unsend is a self-hostable email service platform designed to provide developers and teams with the tools to manage email campaigns, SMTP delivery, and web-based dashboards within a single, modular monorepo structure. It combines backend services with frontend UIs to create a complete solution for email marketing and management.
Architecture
Unsend adopts a monorepo architecture that enables modular development and clear separation of concerns across distinct applications such as marketing, SMTP server, and web dashboard.
- The codebase is organized into workspaces with shared configuration packages to support scalable and maintainable development
- Service classes and queue-based processing are consistently applied across modules to manage asynchronous tasks and business logic
- Design patterns like dependency injection and layered architecture contribute to a well-defined structure
Tech Stack
The project is built using TypeScript and modern JavaScript frameworks to support a robust, type-safe development environment.
- Built with Next.js for marketing and web UIs, and Hono for lightweight API routing and SMTP server functionality
- Relies on Prisma for database interactions, BullMQ for queue management, and Zod for type validation
- Uses tsup and Turbo for build automation, with ESLint and TypeScript for linting and static type checking
Code Quality
Code quality in Unsend shows a mixed state with some structured practices but inconsistent enforcement and limited test coverage.
- Error handling is implemented through try/catch blocks, though not uniformly across all modules
- Code style and conventions vary between components, with minimal automated enforcement of standards
- Linting and type safety are configured, but the absence of comprehensive test suites limits quality assurance
What Makes It Unique
Unsend distinguishes itself by offering a self-hosted email platform that integrates multiple functionalities in a modular architecture.
- The monorepo design enables unified development and deployment while maintaining clear separation between marketing, SMTP, and dashboard layers
- Unique features include campaign scheduling, contact management, and domain verification tailored for self-hosted environments
- The platform provides a developer-friendly API and dashboard that simplify email marketing without sacrificing control or privacy