diff --git a/.dockerignore b/.dockerignore
new file mode 100644
index 000000000000..fccb4c2d2f85
--- /dev/null
+++ b/.dockerignore
@@ -0,0 +1,3 @@
+.git
+.crystal
+.vagrant
diff --git a/Dockerfile b/Dockerfile
index afa811256c49..4e78cd9d50c6 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -10,10 +10,9 @@ RUN curl http://crystal-lang.s3.amazonaws.com/pcl/libpcl-1.12-1-linux-x86_64.tar
 ADD . /opt/crystal-head
 
 WORKDIR /opt/crystal-head
-ENV CRYSTAL_CONFIG_VERSION head
+ENV CRYSTAL_CONFIG_VERSION HEAD
 ENV CRYSTAL_CONFIG_PATH libs:/opt/crystal-head/src:/opt/crystal-head/libs
-
-RUN PATH=$PATH:/opt/llvm-3.5.0-1/bin ./bin/crystal build --release src/compiler/crystal.cr
-
 ENV LIBRARY_PATH /opt/crystal/embedded/lib
-ENV PATH /opt/crystal-head:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
+ENV PATH /opt/crystal-head/bin:/opt/llvm-3.5.0-1/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
+
+RUN make clean crystal release=1