diff --git a/packaging/README.md b/packaging/README.md
index 31f2305..28b89c4 100644
--- a/packaging/README.md
+++ b/packaging/README.md
@@ -15,3 +15,7 @@
   Docker run -i -v /path/to/synergy-scheduler-manager:/tmp/python-synergy-scheduler-manager scheduler-builder-{centos7,ubuntu-14.04}
   ```
   the deb/rpm will be output in `path/to/synergy-scheduler-manager/build`
+
+  You can override the package version that will be set during the packaging
+  process by adding `-e "PKG_VERSION=x.y.z"` to the above command line.
+  Otherwise, the package version will be set to the latest git tag.
diff --git a/packaging/docker/centos7/build.sh b/packaging/docker/centos7/build.sh
index e64037e..e9b9f2d 100644
--- a/packaging/docker/centos7/build.sh
+++ b/packaging/docker/centos7/build.sh
@@ -6,8 +6,10 @@ PKG_DIR=/tmp/python-synergy-scheduler-manager
 
 
 function get_version() {
-    cd $PKG_DIR
-    export PKG_VERSION=$(git tag -l "*.*.*" | sort -V | tail -1)
+    if [[ -z $PKG_VERSION ]]; then
+        cd $PKG_DIR
+        export PKG_VERSION=$(git tag -l "*.*.*" | sort -V | tail -1)
+    fi
 }
 
 function setup() {
diff --git a/packaging/docker/ubuntu-14.04/build.sh b/packaging/docker/ubuntu-14.04/build.sh
index 5a3bcb5..209e4c3 100644
--- a/packaging/docker/ubuntu-14.04/build.sh
+++ b/packaging/docker/ubuntu-14.04/build.sh
@@ -11,8 +11,10 @@ function copy_source() {
 }
 
 function get_version() {
-    cd $PKG_DIR
-    export PKG_VERSION=$(git tag -l "*.*.*" | sort -V | tail -1)
+    if [[ -z $PKG_VERSION ]]; then
+        cd $PKG_DIR
+        export PKG_VERSION=$(git tag -l "*.*.*" | sort -V | tail -1)
+    fi
 }
 
 function setup() {