Postal Email Server

Set up a self-hosted mail server (Postal) to handle outreach emails for a job-application AI agent. A normal email provider wasn't a good fit here, since replies needed to come back into the app automatically for many different users.

What I did:

• Installed and configured Postal on a Linux server using Docker
• Set up SPF, DKIM, MX, and return-path DNS records so emails land in the inbox instead of spam
• Tested real email sending and receiving end-to-end, confirming full authentication pass
• Built a small Python tool that slowly increases daily email volume for a new domain, so it builds trust before sending at full volume
• Connected it to run automatically every day with a cron job

Why it matters: Sending too many emails too fast from a brand-new domain gets flagged as spam. This setup lets a new domain warm up safely, and makes it easy to add more domains later to spread out volume.