smtpctl
secure, reliable, lean, and easy-to configure SMTP server
RUN apt-get update && \
apt-get install -y opensmtpd
RUN apt-get update && \
apt-get install -y opensmtpd
RUN apk add opensmtpd
RUN pacman -S --noconfirm opensmtpd
RUN apt-get update && \
apt-get install -y opensmtpd
RUN dnf install -y opensmtpd
RUN apt-get update && \
apt-get install -y opensmtpd