Open Source Email Platforms

Plunk unifies marketing, transactional, and broadcast emails into a single, complete solution for businesses of all sizes.

Self-hosted email management system with shared inboxes, automation, and powerful collaboration features for efficient customer support.

Self-hosted newsletter platform with powerful features, data protection, and full control over your mailing lists and campaigns.

Open-source email marketing platform offering unlimited subscribers, campaigns, and workspaces. Self-hosted solution with powerful API and beautiful interface.

Self-hosted email API alternative to AWS SES & Mailgun. Open-source AGPL-3.0 with enterprise features, automated deliverability, and cloud version coming 2026.

00 is an open-source email API and infrastructure solution that allows developers to own and control their email stack.

Provides AI agents with real email inboxes via REST API. Create inboxes instantly, send and receive messages, search threads, and handle attachments programmatically.