diff --git a/webmails/rainloop/Dockerfile b/webmails/rainloop/Dockerfile
index 625f1b3f..714390d8 100644
--- a/webmails/rainloop/Dockerfile
+++ b/webmails/rainloop/Dockerfile
@@ -1,7 +1,7 @@
 FROM php:5-apache
 
 RUN apt-get update && apt-get install -y \
-      unzip
+      unzip python3 python3-jinja2
 
 ENV RAINLOOP_URL https://github.com/RainLoop/rainloop-webmail/releases/download/v1.12.0/rainloop-community-1.12.0.zip
 
@@ -22,6 +22,6 @@ COPY php.ini /usr/local/etc/php/conf.d/rainloop.ini
 COPY config.ini /config.ini
 COPY default.ini /default.ini
 
-COPY start.sh /start.sh
+COPY start.py /start.py
 
-CMD ["/start.sh"]
+CMD /start.py
diff --git a/webmails/rainloop/default.ini b/webmails/rainloop/default.ini
index b77281f4..be9a0969 100644
--- a/webmails/rainloop/default.ini
+++ b/webmails/rainloop/default.ini
@@ -1,13 +1,13 @@
-imap_host = "%FRONT_ADDRESS%"
+imap_host = "{{ FRONT_ADDRESS }}"
 imap_port = 10143
 imap_secure = "None"
 imap_short_login = Off
 sieve_use = On
 sieve_allow_raw = Off
-sieve_host = "%IMAP_ADDRESS%"
+sieve_host = "{{ IMAP_ADDRESS }}"
 sieve_port = 4190
 sieve_secure = "None"
-smtp_host = "%FRONT_ADDRESS%"
+smtp_host = "{{ FRONT_ADDRESS }}"
 smtp_port = 10025
 smtp_secure = "None"
 smtp_short_login = Off
diff --git a/webmails/rainloop/start.py b/webmails/rainloop/start.py
new file mode 100755
index 00000000..a9f5da32
--- /dev/null
+++ b/webmails/rainloop/start.py
@@ -0,0 +1,21 @@
+#!/usr/bin/python3
+
+import jinja2
+import os
+import shutil
+
+convert = lambda src, dst: open(dst, "w").write(jinja2.Template(open(src).read()).render(**os.environ))
+
+# Actual startup script
+os.environ["FRONT_ADDRESS"] = os.environ.get("FRONT_ADDRESS", "front")
+os.environ["IMAP_ADDRESS"] = os.environ.get("IMAP_ADDRESS", "imap")
+
+base = "/data/_data_/_default_/"
+shutil.rmtree(base + "domains/", ignore_errors=True)
+os.makedirs(base + "domains", exist_ok=True)
+os.makedirs(base + "configs", exist_ok=True)
+
+convert("/default.ini", "/data/_data_/_default_/domains/default.ini")
+convert("/config.ini", "/data/_data_/_default_/configs/config.ini")
+
+os.execv("/usr/local/bin/apache2-foreground", ["apache2-foreground"])
diff --git a/webmails/rainloop/start.sh b/webmails/rainloop/start.sh
deleted file mode 100755
index f43983d0..00000000
--- a/webmails/rainloop/start.sh
+++ /dev/null
@@ -1,20 +0,0 @@
-#!/bin/sh
-
-template(){
-  sed \
-    -e "s/%FRONT_ADDRESS%/$FRONT_ADDRESS/g" \
-    -e "s/%IMAP_ADDRESS%/$IMAP_ADDRESS/g"
-}
-
-# There is no cleaner way to setup the default SMTP/IMAP server or to
-# override the configuration
-rm -f /data/_data_/_default_/domains/*
-mkdir -p /data/_data_/_default_/domains/ /data/_data_/_default_/configs/
-template </default.ini >/data/_data_/_default_/domains/default.ini
-template </config.ini  >/data/_data_/_default_/configs/config.ini
-
-# Fix some permissions
-chown -R www-data:www-data /data
-
-# Run apache
-exec apache2-foreground