Node.js Bulk Email Sender with Gmail API & SMTP Rotation

I’m looking for an experienced Node.js developer to build a custom bulk email marketing and sending application based on an existing software reference. The system should support Gmail API and SMTP account integration, multiple sending sources, configurable account limits, rotational sending, queue-based processing, OAuth token refresh, HTML email templates, personalization tags, contact import, attachments, and real-time campaign progress. A simple dashboard for managing accounts, campaigns, contacts, and reports is required. The application should be stable, scalable, well-structured, and easy to configure. Experience with Gmail API, SMTP, Node.js, email queues, and high-volume email systems is preferred.