diff --git a/action.yml b/action.yml
index 462ef60..4561066 100644
--- a/action.yml
+++ b/action.yml
@@ -39,41 +39,23 @@ inputs:
 runs:
   using: "composite"
   steps:
-    - name: Initial PR comment
-      # TODO: potentially replace with Action version number over time
-      uses: LocalStack/setup-localstack/prepare@main
-      if: inputs.ci-project && inputs.github-token
-      with:
-        github-token: ${{ inputs.github-token }}
-        ci-project: ${{ inputs.ci-project }}
-
-    - name: Start LocalStack
-      run: |
-        pip install pyopenssl -U
-
-        if [ "$USE_PRO" = true ]; then
-          docker pull localstack/localstack-pro:"$IMAGE_TAG" &
-          CONFIGURATION="$CONFIGURATION DNS_ADDRESS=127.0.0.1"
-        else
-          docker pull localstack/localstack:"$IMAGE_TAG" &
-        fi
-
-        pip install localstack
-        if [ "$INSTALL_AWSLOCAL" = true ]; then
-          pip install awscli-local[ver1]
-        fi
-
-        export CI_PROJECT=${{ inputs.ci-project }}
-        eval "${CONFIGURATION} localstack start -d"
-
-        localstack wait -t 30
-
-      shell: bash
+    # - name: Initial PR comment
+    #   # TODO: potentially replace with Action version number over time
+    #   uses: LocalStack/setup-localstack/prepare@main
+    #   if: inputs.ci-project && inputs.github-token
+    #   with:
+    #     github-token: ${{ inputs.github-token }}
+    #     ci-project: ${{ inputs.ci-project }}
+
+    - name: Start Localstack
+      uses: jenseng/dynamic-uses@v1
       env:
-        IMAGE_TAG: "${{ inputs.image-tag }}"
-        INSTALL_AWSLOCAL: "${{ inputs.install-awslocal }}"
-        USE_PRO: "${{ inputs.use-pro }}"
-        CONFIGURATION: "${{ inputs.configuration }}"
+        action-version: ${{ fromJSON(format('["{0}","{1}"]', github.ref_name, github.head_ref))[github.event_name == 'pull_request'] }}
+      with:
+        # now you can use expressions 🥳
+        uses: LocalStack/setup-localstack/startup@${{ env.action-version }}
+        # the `with` needs to be converted to a valid json string
+        with: "${{ toJSON(inputs) }}"
 
     # TODO: potentially add an additional step here to create preview envs, and add a switch to
     #       enable/disable the "Start LocalStack" action above. This way we could make this action
diff --git a/startup/action.yml b/startup/action.yml
new file mode 100644
index 0000000..861e806
--- /dev/null
+++ b/startup/action.yml
@@ -0,0 +1,67 @@
+name: 'Start up Localstack'
+
+inputs:
+  image-tag:
+    description: 'Tag of the LocalStack Docker image to use'
+    required: true
+    default: 'latest'
+  install-awslocal:
+    description: 'Whether to install the `awslocal` CLI into the environment'
+    required: true
+    default: 'true'
+  use-pro:
+    description: 'Whether to use LocalStack Pro (requires a valid API key)'
+    required: false
+    default: 'false'
+  configuration:
+    description: 'Configuration variables to use for LocalStack'
+    required: false
+    default: ''
+  ci-project:
+    description: 'Name of the CI project to track in LocalStack Cloud'
+    required: false
+    default: ''
+
+runs:
+  using: "composite"
+  steps:
+    # - name: Initial PR comment
+    #   # TODO: potentially replace with Action version number over time
+    #   uses: LocalStack/setup-localstack/prepare@main
+    #   if: inputs.ci-project && inputs.github-token
+    #   with:
+    #     github-token: ${{ inputs.github-token }}
+    #     ci-project: ${{ inputs.ci-project }}
+
+    - name: Start LocalStack
+      run: |
+        pip install pyopenssl -U
+
+        if [ "$USE_PRO" = true ]; then
+          docker pull localstack/localstack-pro:"$IMAGE_TAG" &
+          CONFIGURATION="$CONFIGURATION DNS_ADDRESS=127.0.0.1"
+        else
+          docker pull localstack/localstack:"$IMAGE_TAG" &
+        fi
+
+        pip install localstack
+        if [ "$INSTALL_AWSLOCAL" = true ]; then
+          pip install awscli-local[ver1]
+        fi
+
+        export CI_PROJECT=${{ inputs.ci-project }}
+        eval "${CONFIGURATION} localstack start -d"
+
+        localstack wait -t 30
+
+      shell: bash
+      env:
+        IMAGE_TAG: "${{ inputs.image-tag }}"
+        INSTALL_AWSLOCAL: "${{ inputs.install-awslocal }}"
+        USE_PRO: "${{ inputs.use-pro }}"
+        CONFIGURATION: "${{ inputs.configuration }}"
+
+    # TODO: potentially add an additional step here to create preview envs, and add a switch to
+    #       enable/disable the "Start LocalStack" action above. This way we could make this action
+    #       the single entry point which then delegates to sub-actions in this repo, based on the
+    #       user-provided configuration...