diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..a83bb87
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,2 @@
+build/
+.idea/
diff --git a/Dockerfile b/Dockerfile
index 00b4249..b7624e3 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -2,8 +2,6 @@ FROM alpine:3
 
 LABEL maintainer="Varakh<varakh@varakh.de>"
 
-ENV FILEBIN_VERSION 3.4.1
-
 # Expose variables to ease overwriting
 ENV RECONFIGURE true
 ENV MIGRATE true
@@ -47,14 +45,23 @@ ENV SMALL_UPLOAD_SIZE 5120
 ENV TARBALL_MAX_SIZE 1073741824
 ENV TARBALL_CACHE_TIME 300
 ENV MAX_INVITATION_KEYS 3
+ENV SMTP_ENABLED false
+ENV SMTP_PROTOCOL 'smtp'
+ENV SMTP_HOST ''
+ENV SMTP_PORT 587
+ENV SMTP_CRYPTO 'tls'
+ENV SMTP_USER ''
+ENV SMTP_PASS ''
 
 # add script for database
 ADD src/wait-for.sh /wait-for.sh
 
+# add upstream application
+ADD build/ /var/www
+
 # install dependencies
 RUN chmod -x /wait-for.sh && \
     apk add --update --no-cache \
-        git \
         nginx \
         s6 \
         curl \
@@ -80,17 +87,13 @@ RUN chmod -x /wait-for.sh && \
         php7-pdo \
         php7-pdo_pgsql \
         php7-ctype \
-        php7-pdo_pgsql \
-        php7-mysqli \
         php7-mysqli \
         php7-pecl-memcached \
         memcached \
         ca-certificates && \
     rm -rf /var/cache/apk/* && \
     apk add gnu-libiconv --update-cache --repository http://dl-cdn.alpinelinux.org/alpine/edge/community/ --allow-untrusted && \
-    rm -rf /var/www && \
-    # clone application and prepare www dir
-    git clone --branch ${FILEBIN_VERSION} https://github.com/Bluewind/filebin --depth=1 /var/www && \
+    # prepare www dir
     cp -r /var/www/application/config/example/* /var/www/application/config && \
     # set environments
     sed -i "s|;*memory_limit =.*|memory_limit = ${PHP_MEMORY_LIMIT}|i" /etc/php7/php.ini && \
diff --git a/README.md b/README.md
index 87bf35e..96e08f0 100644
--- a/README.md
+++ b/README.md
@@ -57,6 +57,7 @@ There are two environment variables introduced by this image:
 
 * `RECONFIGURE`: If all defined environment should be re-applied to the provided `.tpl` files within the image. You probably want this to be `1` unless you mounted your `config/` folder on the host
 * `MIGRATE`: Calls FileBin database migration every time the container is started and updates dependencies via `composer`
+* `SMTP_ENABLE`: Set to `true` in order to enable sending mails via an external SMTP server, set to `false` to use PHP's internal mailer, see other `SMTP_` variables in the `Dockerfile`
 
 ### Setting up a nginx proxy
 
@@ -122,3 +123,20 @@ docker exec filebin_db bash -c "/usr/bin/pg_dumpall -U fb|gzip -c > /filebin_db.
 docker cp filebin_db/:/var:/filebin_db.sql.gz /tmp/;
 docker exec filebin_db bash -c "rm /filebin_db.sql.gz";
 ```
+
+## Building
+
+Steps:
+
+* Clone to local `build/` folder which is later added
+* Build image
+* Push to registry or use locally
+
+Example:
+
+```
+export FILEBIN_VERSION=3.4.1
+mkdir -p build
+git clone --branch ${FILEBIN_VERSION} https://github.com/Bluewind/filebin --depth=1 build/
+docker build -t varakh/filebin:${FILEBIN_VERSION} -t varakh/filebin:latest .
+```
\ No newline at end of file
diff --git a/src/config/config-local.php.tpl b/src/config/config-local.php.tpl
index f3b7e9f..e14e39c 100644
--- a/src/config/config-local.php.tpl
+++ b/src/config/config-local.php.tpl
@@ -41,3 +41,13 @@ $config['tarball_cache_time'] = intval(%%%TARBALL_CACHE_TIME%%%);
 
 // The maximum number of active invitation keys per account.
 $config['max_invitation_keys'] = intval(%%%MAX_INVITATION_KEYS%%%);
+
+// SMTP mail settings if enabled
+if (getenv('SMTP_ENABLED') === 'true') {
+    $config['protocol'] = %%%SMTP_PROTOCOL%%%;
+    $config['smtp_host'] = %%%SMTP_HOST%%%;
+    $config['smtp_port'] = intval(%%%SMTP_PORT%%%);
+    $config['smtp_crypto'] = %%%SMTP_CRYPTO%%%;
+    $config['smtp_user'] = %%%SMTP_USER%%%;
+    $config['smtp_pass'] = %%%SMTP_PASS%%%;
+}
\ No newline at end of file
diff --git a/src/configure.php b/src/configure.php
index 8104a67..fbf7e14 100644
--- a/src/configure.php
+++ b/src/configure.php
@@ -19,7 +19,13 @@ if (getenv('RECONFIGURE') === "true") {
         'SMALL_UPLOAD_SIZE',
         'TARBALL_MAX_SIZE',
         'TARBALL_CACHE_TIME',
-        'MAX_INVITATION_KEYS'
+        'MAX_INVITATION_KEYS',
+        'SMTP_PROTOCOL',
+        'SMTP_HOST',
+        'SMTP_PORT',
+        'SMTP_CRYPTO',
+        'SMTP_USER',
+        'SMTP_PASS'
     ];
     contentsReplace($confVars, $confPath, $confTargetPath);