listmonk

Performance and features packed into a single binary. Manage millions of subscribers across many single and double opt-in lists with custom JSON attributes for each subscriber. Query and segment subscribers with SQL expressions. Use the super fast bulk importer (10k records per second) or use HTTP/JSON APIs or interact with the simple table schema to integrate external CRMs and subscriber databases. Visualize and compare campaign performance. Connect external visualization programs to the database easily with the simple table structure. Create powerful, dynamic e-mail templates with the Go templating language. Use template expressions, logic, and 100+ functions in subject lines and content. Write HTML e-mails in a WYSIWYG editor, Markdown, raw syntax-highlighted HTML, or just plain text. Highly configurable, multi-threaded, high-throughput multi-SMTP e-mail queues for super fast campaign delivery.