Although Mailroom is designed to be a framework where you implement your own handlers and transports, we have provided a few built-in integrations for common cases to help get you started.
Use slack.NewTransport() to create a Mailroom transport that can send notifications via Slack. It supports rich formatting (blocks, attachments, etc.).
Use postgres.NewUserStore() to create a Mailroom user store that persists user information in a PostgreSQL database.
user.NewInMemoryStore() provides a simple yet complete in-memory user store implementation. It's especially useful for testing and development.
(It's stable enough to use for single-replica production deployments too, if needed - just realize that known identifiers and user preferences will be lost on restart).