Docker

RustMail ships a multi-arch Docker image supporting linux/amd64, linux/arm64, and linux/arm/v7.

Quick Start

docker run -p 1025:1025 -p 8025:8025 smyile/rustmail:latest

Docker Compose

services:
  rustmail:
    image: smyile/rustmail:latest
    ports:
      - "1025:1025"
      - "8025:8025"
    security_opt:
      - no-new-privileges:true
    volumes:
      - rustmail-data:/data
    restart: unless-stopped

volumes:
  rustmail-data:

Persistence

Mount a volume to /data to persist emails across container restarts. The image sets RUSTMAIL_DB_PATH=/data/rustmail.db and RUSTMAIL_BIND=0.0.0.0 by default.

For ephemeral (CI) usage, skip the volume:

docker run -p 1025:1025 -p 8025:8025 -e RUSTMAIL_EPHEMERAL=true smyile/rustmail:latest

Environment Variables

All CLI flags have corresponding environment variables prefixed with RUSTMAIL_. These work in Docker Compose environment blocks, .env files, or docker run -e flags.

Optional STARTTLS

RustMail supports explicit SMTP STARTTLS on the existing SMTP listener port. To enable it in Docker, mount a certificate and key, then set both RUSTMAIL_SMTP_TLS_CERT and RUSTMAIL_SMTP_TLS_KEY.

docker run \
  -p 1025:1025 -p 8025:8025 \
  -v "$PWD/certs:/certs:ro" \
  -e RUSTMAIL_SMTP_TLS_CERT=/certs/smtp-cert.pem \
  -e RUSTMAIL_SMTP_TLS_KEY=/certs/smtp-key.pem \
  smyile/rustmail:latest

RustMail advertises STARTTLS only when both files are configured. After a client upgrades the connection, it must send EHLO again.