diff --git a/build_container/Dockerfile-ubuntu b/build_container/Dockerfile-ubuntu
index bfdcd1c8..58877d07 100644
--- a/build_container/Dockerfile-ubuntu
+++ b/build_container/Dockerfile-ubuntu
@@ -6,9 +6,12 @@ ENV CLOUDSDK_PYTHON=python3
 COPY ./build_container_common.sh /
 COPY ./build_container_ubuntu.sh /
 
-RUN ./build_container_ubuntu.sh
-
-ENV LANG en_US.utf8
+ENV ANDROID_SDK_INSTALL_TARGET /.android
 ENV ANDROID_HOME /.android/sdk
 ENV ANDROID_SDK_ROOT /.android/sdk
+ENV ANDROID_NDK_VERSION 21.4.7075529
 ENV ANDROID_NDK_HOME /.android/sdk/ndk/21.4.7075529
+
+RUN ./build_container_ubuntu.sh
+
+ENV LANG en_US.utf8
diff --git a/build_container/build_container_ubuntu.sh b/build_container/build_container_ubuntu.sh
index 6c0719b1..ee5bea76 100755
--- a/build_container/build_container_ubuntu.sh
+++ b/build_container/build_container_ubuntu.sh
@@ -156,10 +156,8 @@ function install_android_tools() {
     # Install Android tools
     #######################
 
-    sdk_install_target="/.android"
-    android_home="$sdk_install_target/sdk"
-    mkdir -p "$android_home"
-    pushd "$sdk_install_target"
+    mkdir -p "$ANDROID_HOME"
+    pushd "$ANDROID_SDK_INSTALL_TARGET"
 
     cmdline_file="commandlinetools-linux-7583922_latest.zip"
     curl -OL "https://dl.google.com/android/repository/$cmdline_file"
@@ -167,8 +165,8 @@ function install_android_tools() {
     mkdir -p sdk/cmdline-tools/latest
     mv cmdline-tools/* sdk/cmdline-tools/latest
 
-    sdkmanager=$android_home/cmdline-tools/latest/bin/sdkmanager
-    echo "y" | $sdkmanager --install "ndk;21.4.7075529"
+    sdkmanager=$ANDROID_HOME/cmdline-tools/latest/bin/sdkmanager
+    echo "y" | $sdkmanager --install "ndk;$ANDROID_NDK_VERSION"
     $sdkmanager --install "platforms;android-30"
     $sdkmanager --install "build-tools;30.0.2"