diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 8b976cc..d995f28 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -1,17 +1,31 @@
 stages:
 - build
+- build-manifest
 
 variables:
-  CACHETAG: build-${VERSION}
+  VERSION: latest
   DOCKER_HOST: tcp://docker:2375
+  VERSIONARCH: ${VERSION}-${ARCH}
 
+cache:
+  key: ${CI_JOB_NAME_SLUG}-${CI_COMMIT_REF_SLUG}
+  paths:
+  - build-cache
+
+image: docker:latest
 services:
 - docker:dind
 
 before_script:
-- docker info
-- docker version
+- if [ ! -d build-cache ]; then mkdir build-cache; fi
+- sed -ie s'/https/http/' /etc/apk/repositories
+- HTTP_PROXY=http://proxy.dege.lan:3128 apk add git curl
+- docker info && docker version
+# env|sort
 - echo "$CI_JOB_TOKEN" | docker login -u "$CI_REGISTRY_USER" "$CI_REGISTRY" --password-stdin
-- env|sort
 
-include: .gitlab-docker-x86_64.yml
+include:
+- .gitlab-docker-x86_64.yml
+# .gitlab-docker-armv7l.yml
+# .gitlab-docker-arm64.yml
+- .gitlab-docker-manifest.yml
diff --git a/.gitlab-docker-manifest.yml b/.gitlab-docker-manifest.yml
new file mode 100644
index 0000000..8b38379
--- /dev/null
+++ b/.gitlab-docker-manifest.yml
@@ -0,0 +1,10 @@
+x86_64:build-manifest:
+  stage: build-manifest
+  script:
+  - docker manifest create ${CI_REGISTRY_IMAGE}:${VERSION} ${CI_REGISTRY_IMAGE}:${VERSION}-x86_64 #${CI_REGISTRY_IMAGE}:${VERSION}-arm64 ${CI_REGISTRY_IMAGE}:${VERSION}armv7l
+  - docker manifest push --purge ${CI_REGISTRY_IMAGE}:${VERSION}
+  tags:
+  - docker
+  - x86_64
+  only:
+  - master
diff --git a/.gitlab-docker-x86_64.yml b/.gitlab-docker-x86_64.yml
index 7a80415..77741bd 100644
--- a/.gitlab-docker-x86_64.yml
+++ b/.gitlab-docker-x86_64.yml
@@ -1,14 +1,14 @@
 x86_64:build:
   variables:
-    VERSION: x86_64
+    ARCH: x86_64
   stage: build
-  image: docker:latest
   script:
   - if [ -f init ]; then chmod 500 init; fi
-  - ([ -z "$REFRESH" ] && docker pull ${CI_REGISTRY_IMAGE}:${CACHETAG}) || echo "true"
-  - docker build --cache-from ${CI_REGISTRY_IMAGE}:${CACHETAG} -t ${CI_REGISTRY_IMAGE}:${VERSION} -t ${CI_REGISTRY_IMAGE}:${CACHETAG} .
-  - docker push ${CI_REGISTRY_IMAGE}:${VERSION}
-  - docker push ${CI_REGISTRY_IMAGE}:${CACHETAG}
+  - ([ -z "$REFRESH" -a -f build-cache/${CI_COMMIT_REF_SLUG} ]) && docker load < build-cache/${CI_COMMIT_REF_SLUG} || true
+  - rm build-cache/* || true
+  - docker build --build-arg HTTP_PROXY=http://proxy.dege.lan:3128 --cache-from ${CI_REGISTRY_IMAGE}:${VERSIONARCH} -t ${CI_REGISTRY_IMAGE}:${VERSIONARCH} .
+  - docker push ${CI_REGISTRY_IMAGE}:${VERSIONARCH}
+  - docker save ${CI_REGISTRY_IMAGE}:${VERSIONARCH} > build-cache/${CI_COMMIT_REF_SLUG}
   tags:
   - docker
   - x86_64
diff --git a/Dockerfile b/Dockerfile
index 803b326..198fcd0 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,20 +1,38 @@
 # NAME leenooks/smtp
 # VERSION latest
 
-FROM debian:stretch-slim
+FROM alpine
 
-RUN apt-get update \
-	&& apt-get install sendmail sasl2-bin milter-greylist -yyq \
-	&& sed -ie 's/mech_list: EXTERNAL DIGEST-MD5 CRAM-MD5/mech_list:/' /etc/mail/sasl/Sendmail.conf.2 \
-	&& cd /etc/mail && make clean \
-	&& rm -rf /var/lib/apt/lists/* /tmp/*
+# Change to http respositories, so they we can cache the install packages
+RUN if [ -n ${HTTP_PROXY} ] ; then sed -ie s'/https/http/' /etc/apk/repositories; fi
 
-RUN useradd -rc "HUB Mail Relay" -M relay -NG mail -s /sbin/nologin && echo relay:SmTpR3l2Y | chpasswd
+RUN apk add shadow && useradd -rc "HUB Mail Relay" -M relay -NG mail -s /sbin/nologin && echo relay:SmTpR3l2Y | chpasswd
 
+RUN apk add --no-cache postfix opendkim opendkim-utils \
+  && gpasswd -a postfix opendkim
+
+# Config postfix
+RUN sed -ie 's%#mynetworks = hash:/etc/postfix/network_table%mynetworks = /etc/opendkim/signing/TrustedHosts%' /etc/postfix/main.cf \
+  && echo -n 'bWVzc2FnZV9zaXplX2xpbWl0ID0gMjU2MDAwMDAKcXVldWVfbWluZnJlZSA9IDUxMjAwMDAwCg=='|base64 -d >> /etc/postfix/main.cf
+
+# Enable DKIM
+RUN mkdir /run/opendkim \
+  && echo -n 'IyBNaWx0ZXIgY29uZmlndXJhdGlvbiAtIG9wZW5ka2ltCiMgSWYgdGhlIE9wZW5ES0lNIG1pbHRl\
+ciBpc24ndCBhdmFpbGFibGUsIGFjY2VwdCB0aGUgbWVzc2FnZSBhbnl3YXkuCm1pbHRlcl9kZWZh\
+dWx0X2FjdGlvbiA9IGFjY2VwdAojIFdoYXQgbWlsdGVyIGNvbW11bmljYXRpb24gcHJvdG9jb2wg\
+c2hvdWxkIGJlIHVzZWQgdG8gcGFzcyBtZXNzYWdlcwojIHRvIGFuZCBmcm9tIE9wZW5ES0lNPwpt\
+aWx0ZXJfcHJvdG9jb2wgPSA2CiMgV2hlcmUgc2hvdWxkIHRoZSBPcGVuREtJTSBtaWx0ZXIgYmUg\
+Y29udGFjdCB0aHJvdWdoPyAgTm90ZSB0aGF0IHRoaXMKIyBpcyBpbnNpZGUgdGhlIC92YXIvc3Bv\
+b2wvcG9zdGZpeCBjaHJvb3QuCnNtdHBkX21pbHRlcnMgPSBpbmV0OjEyNy4wLjAuMTo4ODkxCiMg\
+U2VuZCBtYWlsIHRoYXQgZG9lc24ndCBhcnJpdmUgZnJvbSB0aGUgbmV0d29yayB0aHJvdWdoIHRo\
+ZSBzYW1lIG1pbHRlcgojIGFzIG91dGJvdW5kIG1haWwuCm5vbl9zbXRwZF9taWx0ZXJzID0gJHNt\
+dHBkX21pbHRlcnMK' |base64 -d >> /etc/postfix/main.cf
+COPY opendkim.conf /etc/opendkim
+
+VOLUME ["/var/spool/postfix"]
 EXPOSE 25
 
 COPY init /sbin/
 
 # Starting
 ENTRYPOINT [ "/sbin/init" ]
-CMD [ "start" ]
diff --git a/custom.cf b/custom.cf
new file mode 100644
index 0000000..ceed209
--- /dev/null
+++ b/custom.cf
@@ -0,0 +1,2 @@
+message_size_limit = 25600000
+queue_minfree = 51200000
diff --git a/init b/init
index 575bd0c..13eb0e1 100755
--- a/init
+++ b/init
@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/bin/sh
 set -e
 
 NAME="SMTP"
@@ -11,14 +11,17 @@ function stop {
 
 trap 'stop' SIGTERM
 
-if [ -z `hostname --domain` ]; then
-	echo "You must start this container with --hostname= specifying a domain name"
-	exit 1
-fi
+if [ -z "$@" ]; then
+	if [ -z `hostname -d` ]; then
+		echo "You must start this container with --hostname= specifying a domain name"
+		exit 1
+	fi
 
-if [ "$1" == "start" ]; then
-	/usr/sbin/saslauthd -m /run/saslauthd -a pam
-	cd /etc/mail && make && make && exec /usr/sbin/sendmail -q1h -bD &
+	#/usr/sbin/saslauthd -m /run/saslauthd -a pam
+	#cd /etc/mail && make && make && exec /usr/sbin/sendmail -q1h -bD &
+	newaliases
+	postfix start
+	/usr/sbin/opendkim -P /run/opendkim.pid -u opendkim -f
 
 	wait
 else
diff --git a/opendkim.cf b/opendkim.cf
new file mode 100644
index 0000000..5fcdc96
--- /dev/null
+++ b/opendkim.cf
@@ -0,0 +1,12 @@
+# Milter configuration - opendkim
+# If the OpenDKIM milter isn't available, accept the message anyway.
+milter_default_action = accept
+# What milter communication protocol should be used to pass messages
+# to and from OpenDKIM?
+milter_protocol = 6
+# Where should the OpenDKIM milter be contact through?  Note that this
+# is inside the /var/spool/postfix chroot.
+smtpd_milters = inet:127.0.0.1:8891
+# Send mail that doesn't arrive from the network through the same milter
+# as outbound mail.
+non_smtpd_milters = $smtpd_milters
diff --git a/opendkim.conf b/opendkim.conf
new file mode 100644
index 0000000..fcf4252
--- /dev/null
+++ b/opendkim.conf
@@ -0,0 +1,37 @@
+BaseDirectory		/run/opendkim
+Mode			sv
+SubDomains		no
+
+LogResults		yes
+LogWhy			yes
+Syslog			yes
+SyslogSuccess		yes
+
+Canonicalization	relaxed/simple
+
+#Domain			example.com
+#Selector		default
+#KeyFile		/var/db/dkim/example.com.private
+KeyTable		refile:/etc/opendkim/signing/KeyTable
+SigningTable		refile:/etc/opendkim/signing/SigningTable
+ExternalIgnoreList      refile:/etc/opendkim/signing/TrustedHosts
+InternalHosts		refile:/etc/opendkim/signing/TrustedHosts
+
+Background		yes
+Socket			inet:8891@localhost
+#Socket			local:opendkim.sock
+
+ReportAddress		postmaster@example.com
+SendReports		yes
+
+## Hosts to sign email for - 127.0.0.1 is default
+## See the OPERATION section of opendkim(8) for more information
+#
+#InternalHosts		192.168.0.0/16, 10.0.0.0/8, 172.16.0.0/12
+
+## For secondary mailservers - indicates not to sign or verify messages
+## from these hosts
+#
+# PeerList		X.X.X.X
+
+PidFile			/run/opendkim.pid