About the Role

Research Connect is seeking a skilled DevOps + Backend Engineer with 2–6 years of hands-on experience. This role is crucial for developing and scaling our cold email CRM system, with a particular focus on email-based CRM functionalities, cold emailing, inbox syncing, and robust infrastructure scaling.

We are building a cutting-edge Cold Email CRM utilizing the MERN stack. This system will be designed to:

• Seamlessly sync user inboxes and sent boxes using IMAP protocols.
• Manage and execute large-scale cold email campaigns, aiming for 10,000–50,000+ emails per day.
• Implement advanced rotating IP infrastructure strategies to ensure optimal deliverability and maintain domain reputation.

Currently hosted on Hostinger, we are embarking on a comprehensive migration to AWS. A key challenge we are addressing is a significant memory spike issue stemming from IMAP syncing. We require an engineer capable of designing and implementing a scalable, stable, and budget-conscious architecture to resolve these issues and support future growth.

Top Priority Responsibilities

• Resolve the critical memory spike issue caused by email syncing within our Node.js IMAP integration. Ensure efficient inbox and sent box syncing without server instability or crashes. This involves profiling and fixing memory leaks, optimizing inefficient loops, and managing garbage collection across all relevant services.
• Implement robust IP rotation strategies for cold emailing operations (utilizing Postfix, SMTP, Mailgun, Sendgrid, etc.). The system must support high volumes (10,000–50,000 emails/day) while actively preventing placement on spam blacklists.
• Develop a dynamic sync queue architecture for email syncing:
  • Support up to 50 concurrent IMAP inbox/sentbox syncs within a strict monthly infrastructure budget of ₹30,000.
  • Implement a queuing system to manage additional users' syncs when the concurrency limit is reached, providing a popup Estimated Time of Arrival (ETA) based on inbox size and current queue position.
  • Design the system to dynamically handle between 100–500 inbox syncs per day, or accurately determine the realistic upper limit achievable within the given budget, and define a graceful overflow handling mechanism for users exceeding this limit without sync failures.
• Integrate RAM/CPU-aware queuing logic to intelligently delay sync jobs and prevent server overload.
• Proactively monitor usage trends, MongoDB memory consumption, and backend logs to detect and address potential issues before they impact performance.
• Lead the migration from Hostinger to AWS, architecting an auto-scalable, budget-conscious infrastructure optimized for cost-efficiency and performance.
• Set up comprehensive automated health checks (monitoring RAM, CPU, disk space, uptime, and logs) and integrate alert systems for immediate notification of any anomalies.
• Collaborate closely with developers to refactor high-memory consuming endpoints and prepare the infrastructure for 10x user scaling.

Additional Responsibilities

• Build and maintain efficient CI/CD pipelines for Node.js and React applications.
• Optimize MongoDB performance through effective indexing, query tuning, and memory usage management.
• Implement and manage Infrastructure as Code practices, with a preference for Terraform or Ansible.
• Set up comprehensive observability dashboards using tools like PM2, Grafana, and the ELK stack.
• Prepare the AWS environment for auto-scaling, implement effective load balancing, and establish diligent cost monitoring practices.

Required Experience & Skills

• 2–6 years of backend/DevOps experience with a strong command of Node.js, MongoDB, Express, and AWS.
• Deep understanding of IMAP, email syncing mechanisms, SMTP, and the intricacies of cold email infrastructure.
• Strong theoretical and practical grasp of memory profiling techniques, heap snapshot analysis, Garbage Collection (GC) principles, and effective queue management strategies.
• Proven experience in setting up IP rotation (via Postfix, Mailgun, Sendgrid, etc.) and implementing successful domain/IP warm-up strategies.
• Practical experience with worker queue systems (e.g., BullMQ, Redis, RabbitMQ), cron job orchestration, and implementing back-pressure mechanisms.
• Demonstrated ability to design resource-efficient systems that strictly adhere to infrastructure budget constraints (target: ₹30,000/month).
• Proficiency with key AWS services including EC2, S3, RDS, ECS, ALB/NLB, and a strong focus on infrastructure cost optimization.
• Familiarity with essential monitoring and logging tools such as Grafana, PM2, Prometheus, and the ELK stack.