diff --git a/.dockerignore b/.dockerignore
new file mode 100644
index 00000000..97bba075
--- /dev/null
+++ b/.dockerignore
@@ -0,0 +1,4 @@
+.gradle/
+.idea/
+.git/
+Dockerfile
diff --git a/Dockerfile b/Dockerfile
index c07a2caa..c4662f00 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -5,12 +5,13 @@ ARG DOCKER_IMAGE_VERSION=unknown
 
 # JDK version
 ARG JDK=9
-ARG TMP_DIR=muwire-tmp
 
+# Important directories
+ARG TMP_DIR=/muwire-tmp
 ENV APP_HOME=/muwire
 
 # Define working directory.
-WORKDIR /$TMP_DIR
+WORKDIR $TMP_DIR
 
 # Put sources into dir
 COPY . .