diff --git a/action.yml b/action.yml
index 8974fa8..b83911e 100644
--- a/action.yml
+++ b/action.yml
@@ -2,8 +2,9 @@ name: "ssh-setup"
 description: "add a private ssh key"
 inputs:
   run-as:
+    default: "root"
     description: "user to create ssh keys for"
-    required: true
+    required: false
   ssh-key:
     description: "private ssh key"
     required: true
@@ -15,12 +16,12 @@ runs:
   steps:
     - name: mkdir -p ~/.ssh
       shell: bash
-      run: su {{ inputs.run-as }} -c "mkdir -p ~/.ssh"
+      run: su ${{ inputs.run-as }} -c "mkdir -p ~/.ssh"
     - name: add hosts
       shell: bash
-      run: su {{ inputs.run-as }} -c "echo "${{ inputs.add-hosts }}" | xargs ssh-keyscan > ~/.ssh/known_hosts"
+      run: su ${{ inputs.run-as }} -c "echo "${{ inputs.add-hosts }}" | xargs ssh-keyscan > ~/.ssh/known_hosts"
     - name: add ssh key
       shell: bash
       run: |
-        su {{ inputs.run-as }} -c "echo "${{ inputs.ssh-key }}" | tr -d \"\r\" > ~/.ssh/id_ed25519"
-        su {{ inputs.run-as }} -c "chmod -R 600 ~/.ssh"
+        su ${{ inputs.run-as }} -c "echo "${{ inputs.ssh-key }}" | tr -d \"\r\" > ~/.ssh/id_ed25519"
+        su ${{ inputs.run-as }} -c "chmod -R 600 ~/.ssh"