diff --git a/docker.sh b/docker.sh
index ccd396c5..4d2401e1 100755
--- a/docker.sh
+++ b/docker.sh
@@ -90,6 +90,57 @@ declare_if_inside_docker(){
     fi
 }
 
+docker_compose_path_version(){
+    local path="$1"
+    local dir_base="$2"
+    if [ -z "${DOCKER_SERVICE:-}" ]; then
+        echo "Error: \$DOCKER_SERVICE has not been set in environment yet, was check_docker_available() called first?"
+        exit 1
+    fi
+    set +e
+    local version="$(docker-compose exec "$DOCKER_SERVICE" ls "$path" -1 --color=no |
+                     grep --color=no -- "$dir_base" |
+                     tr -d '\r' |
+                     tee /dev/stderr |
+                     tail -n 1 |
+                     sed "s/$dir_base//"
+                    )"
+    set -e
+    if [ -z "$version" ]; then
+        echo "Error: failed to find docker compose path version from path $path for $dir_base!"
+        exit 1
+    fi
+    echo "$version"
+}
+
+docker_compose_version_test(){
+    local name="${1:-}"
+    local version="${2:-}"
+    if [ -z "$name" ]; then
+        "ERROR: missing first arg for name to docker_compose_version_test()"
+        exit 1
+    fi
+    if [ -z "$version" ]; then
+        "ERROR: missing second arg for version to docker_compose_version_test()"
+        exit 1
+    fi
+    if [ "$version" = "latest" ]; then
+        echo "latest version, fetching latest version from DockerHub master branch"
+        local version="$(dockerhub_latest_version "$name")"
+        echo "expecting version '$version'"
+    fi
+    hr
+    found_version="$(docker_compose_path_version / "$name"-)"
+    echo "found $name version $found_version"
+    hr
+    if [[ "$found_version" =~ $version* ]]; then
+        echo "$name docker version matches expected (found '$found_version', expected '$version')"
+    else
+        echo "Docker container version does not match expected version! (found '$found_version', expected '$version')"
+        exit 1
+    fi
+}
+
 docker_compose_port(){
     local env_var="${1:-}"
     local name="${2:-}"
@@ -140,7 +191,7 @@ dockerhub_latest_version(){
         echo "Error: no repo passed to dockerhub_latest_version for first arg"
     fi
     set +e
-    local version="$(curl -s "https://raw.githubusercontent.com/HariSekhon/Dockerfiles/master/$repo/Dockerfile" | awk -F= '/^ARG[[:space:]]+[A-Za-z_]+_VERSION=/ {print $2; exit}')"
+    local version="$(curl -s "https://raw.githubusercontent.com/HariSekhon/Dockerfiles/master/$repo/Dockerfile" | awk -F= '/^ARG[[:space:]]+[A-Za-z0-9_]+_VERSION=/ {print $2; exit}')"
     set -e
     if [ -z "$version" ]; then
         version='.*'
diff --git a/utils.sh b/utils.sh
index ff26b875..47e268bf 100755
--- a/utils.sh
+++ b/utils.sh
@@ -244,7 +244,7 @@ print_debug_env(){
         #eval echo "export ${name}_PORT=$`echo ${name}_PORT`"
         # instead of just name_PORT, find all PORTS in environment and print them
         # while read line to preserve CASSANDRA_PORTS=7199 9042
-        env | egrep "^$name.*_" | grep -v -e 'DEFAULT$' -e 'VERSIONS$' | sort | while read env_var; do
+        env | egrep "^$name.*_" | grep -v -e 'DEFAULT=' -e 'VERSIONS=' | sort | while read env_var; do
             # sed here to quote export CASSANDRA_PORTS=7199 9042 => export CASSANDRA_PORTS="7199 9042"
             eval echo "'export $env_var'" | sed 's/=/="/;s/$/"/'
         done
@@ -575,6 +575,11 @@ retry(){
     else
         sleep_secs=1
     fi
+    local negate=""
+    if [ "$1" == '!' ]; then
+        negate=1
+        shift
+    fi
     local cmd="${@:-}"
     if [ -z "$cmd" ]; then
         echo "ERROR: no command passed to retry() for \$3"
@@ -586,8 +591,13 @@ retry(){
     while true; do
         let try_number+=1
         echo -n "try $try_number:  "
-        if $cmd; then
-            timestamp "Succeeded after $SECONDS secs"
+        if [ -n "$negate" ]; then
+            if ! $cmd; then
+                timestamp "Command failed after $SECONDS secs"
+                break
+            fi
+        elif $cmd; then
+            timestamp "Command succeeded after $SECONDS secs"
             break
         fi
         if [ $SECONDS -gt $max_secs ]; then