diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 66589bc..ff552af 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -3,7 +3,7 @@ name: Docker Run Action Tests
 on:
   push:
     branches:
-      - main
+      - '**'
   pull_request:
 
 jobs:
diff --git a/README.md b/README.md
index 8bdac31..15682c8 100644
--- a/README.md
+++ b/README.md
@@ -55,4 +55,4 @@
     run: |
       echo "first line"
       echo "second line"
-```
+
diff --git a/action.yml b/action.yml
index 7c1a8e6..ed8cba2 100644
--- a/action.yml
+++ b/action.yml
@@ -15,6 +15,10 @@ inputs:
     description: 'Use a specific shell'
     required: false
     default: sh
+  script_prefix: 
+    description: 'a prefix telling the shell to execute the following (single) string as a script'
+    required: false
+    default: -c
   registry:
     description: 'Registry'
     required: false
diff --git a/entrypoint.sh b/entrypoint.sh
index 39c1d70..020396a 100755
--- a/entrypoint.sh
+++ b/entrypoint.sh
@@ -8,4 +8,4 @@ if [ ! -z $INPUT_DOCKER_NETWORK ];
 then INPUT_OPTIONS="$INPUT_OPTIONS --network $INPUT_DOCKER_NETWORK"
 fi
 
-exec docker run -v "/var/run/docker.sock":"/var/run/docker.sock" $INPUT_OPTIONS --entrypoint=$INPUT_SHELL $INPUT_IMAGE -c "${INPUT_RUN//$'\n'/;}"
+exec docker run -v "/var/run/docker.sock":"/var/run/docker.sock" $INPUT_OPTIONS $INPUT_IMAGE $INPUT_SHELL $INPUT_SCRIPT_PREFIX "${INPUT_RUN//$'\n'/;}"