* [Cloud Mail v3.2.0](https://github.com/maillab/cloud-mail) – Serverless email platform built on Cloudflare Workers with web and API support.

* [Premailer v1.30.0](https://github.com/premailer/premailer) – Converts CSS into inline styles, fixes relative paths, checks CSS for email-client compatibility, and generates plain-text output.

* [MailTime 5.0.0](https://github.com/veliovgroup/mail-time) – Email queuing system that extends Nodemailer with multi-SMTP rotation, storage-backed retries, and horizontal scaling support.

* [SpamEater v4.1.0](https://github.com/rufftruffles/spameater) – Privacy-focused disposable email service that auto-deletes messages after 24 hours and includes ModSecurity WAF protection.

* [Mailtrap Node.js client v4.9.0](https://github.com/mailtrap/mailtrap-nodejs) – Node.js client for sending transactional and bulk emails with sandbox mode, attachments, and API token-based authentication.

* [go-premailer v1.35.0](https://github.com/vanng822/go-premailer) – Inlines CSS into HTML email for Go.

* [Upyo 0.5.2](https://github.com/dahlia/upyo) – Cross-runtime library for sending email messages using SMTP and various providers.