diff --git a/Dockerfile b/Dockerfile
index 077acd8..8863e6d 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -2,7 +2,12 @@ FROM jcgruenhage/baseimage-alpine
 MAINTAINER Jan Christian Grünhage <jan.christian@gruenhage.xyz>
 
 ENV	UID=192 \
-	GID=192
+	GID=192 \
+	STAGING=1 \
+	CHALLENGE="dns-01"
+
+# Set STAGING to false(0) by default, set to true(1) to use staging LE-Endpoint
+# Set CHALLENGE to "dns-01" (DNS Challenge) by default, set to "http-01" to use the HTTP Challenge
 
 RUN apk update \
 	&& apk add --upgrade \
@@ -14,12 +19,14 @@ RUN apk update \
 		bash \
 		su-exec \
 		libxml2-utils \
-	&& git clone https://github.com/lukas2511/dehydrated /dehydrated 
+	&& git clone https://github.com/lukas2511/dehydrated /dehydrated
 
+# Add the files in the 'root' folder to the images filesystem
 ADD root /
 
-
 VOLUME /etc/dehydrated
 VOLUME /var/www/dehydrated
 VOLUME /certs
 
+# Execute the setup script
+RUN bash /etc/once/setup.sh
diff --git a/root/etc/once/setup.sh b/root/etc/once/setup.sh
new file mode 100644
index 0000000..f17af00
--- /dev/null
+++ b/root/etc/once/setup.sh
@@ -0,0 +1,23 @@
+#!/bin/bash
+
+# Copy the example config file to the config location
+cp /dehydrated/docs/examples/config /etc/dehydrated/config
+
+# Use the staging endpoint?
+if [ $STAGING -ne 0 ]; then
+	sed -ie 's/#CA=.*$/CA="https:\/\/acme-staging.api.letsencrypt.org\/directory"/g' /etc/dehydrated/config
+	sed -ie 's/#CA_TERMS=.*$/CA_TERMS="https:\/\/acme-staging.api.letsencrypt.org\/terms"/g' /etc/dehydrated/config
+fi
+
+# Set the challenge-type
+case "$CHALLENGE" in
+	"http-01")
+		sed -ie 's/#CHALLENGETYPE=.*$/CHALLENGETYPE="http-01"/g' /etc/dehydrated/config
+	;;
+	"dns-01")
+		sed -ie 's/#CHALLENGETYPE=.*$/CHALLENGETYPE="dns-01"/g' /etc/dehydrated/config
+	;;
+	*)
+		echo "WARNING: Unknown Challenge type! Using default from dehydrated"
+	;;
+esac