diff --git a/docker_build.sh b/docker_build.sh
old mode 100644
new mode 100755
diff --git a/docker_push.sh b/docker_push.sh
old mode 100644
new mode 100755
index 71650bd..2f0c650
--- a/docker_push.sh
+++ b/docker_push.sh
@@ -12,8 +12,8 @@ docker_push(){
 # TRAVIS_TAG: If the current build is for a git tag, this variable is set to the tag’s name.
 # TRAVIS_PULL_REQUEST_BRANCH: if the current job is a pull request, the name of the branch from which the PR originated.
 
-if [[ "$TRAVIS_PULL_REQUEST_BRANCH" == "" ]]; then
-    if [[ "$TRAVIS_TAG" =! "" ]]; then
+if [[ -z "$TRAVIS_PULL_REQUEST_BRANCH" ]]; then
+    if [[ -n "$TRAVIS_TAG" ]]; then
         # Tagging should trigger a release in Docker Hub, that's immutable.
         echo "git tag action, push the tag"
         docker_push "$TRAVIS_TAG-release"
@@ -21,7 +21,7 @@ if [[ "$TRAVIS_PULL_REQUEST_BRANCH" == "" ]]; then
         # we push to latest when master is built and that's not a pull request
         echo "master build, push to latest"
         docker_push "latest"
-    elif [[ "$TRAVIS_BRANCH" ~= "v*" ]]; then
+    elif [[ "$TRAVIS_BRANCH" == "v"* ]]; then
         # this is a version branch and we push it.
         echo "branch build, push to branch-latest"
         docker_push "$TRAVIS_BRANCH-latest"