Mailcow Deliverability & Infrastructure Expert Needed (Proofpoint, IP Reputation, ISP Rotation)

We are looking for an experienced Mailcow / Email Deliverability Engineer to manage and optimize our self-hosted email infrastructure. The ideal candidate has deep experience with Mailcow, Postfix, email reputation management, ISP/IP rotation strategies, Proofpoint remediation, DNS authentication, and large-scale email sending. We need someone who can take ownership of the infrastructure and ensure long-term inbox placement and domain health. Responsibilities Manage and maintain our Mailcow infrastructure Troubleshoot deliverability issues across Gmail, Outlook, Microsoft 365, Yahoo, and corporate email providers Handle Proofpoint blocklists and whitelisting requests Monitor and maintain IP reputation and domain reputation Configure and optimize: SPF DKIM DMARC PTR/rDNS HELO/EHLO MTA-STS Implement and manage IP rotation strategies across multiple ISPs/providers Set up IP warm-up and domain warm-up processes Monitor blacklists and reputation services Optimize sending limits, throttling, and routing Create systems to automatically detect and replace degraded IPs Ensure high inbox placement and low spam rates Provide ongoing monitoring, reporting, and maintenance Required Experience Expert-level Mailcow administration Strong Postfix knowledge Email deliverability and reputation management Proofpoint troubleshooting and delisting processes Multi-IP sending infrastructure SMTP routing and relay management DNS authentication best practices Experience with large-scale outbound email operations Linux system administration (Ubuntu/Debian) Nice to Have Experience with Amazon SES, Mailgun, SendGrid, or other SMTP relays Experience with Instantly, Smartlead, Salesforge, or similar platforms Automation and scripting skills Monitoring and alerting systems Current Goals Resolve Proofpoint delivery issues Improve inbox placement Maintain healthy domain and IP reputation Scale sending volume safely Build a sustainable infrastructure that can rotate traffic between multiple IPs/providers when needed When Applying Please provide: Examples of Mailcow infrastructures you have managed Experience handling Proofpoint reputation issues Experience with IP rotation and deliverability management Monthly email volume you have managed Your recommended approach for maintaining inbox placement at scale Important: We are looking for a long-term partner who can proactively manage deliverability, reputation, monitoring, and infrastructure health—not just perform an initial setup. Deliverability ownership is a key part of this role.