diff --git a/.github/workflows/deploy.yml b/.github/workflows/deploy.yml
index 2ce5634..a9d8b57 100644
--- a/.github/workflows/deploy.yml
+++ b/.github/workflows/deploy.yml
@@ -35,6 +35,11 @@ jobs:
           KEY: ${{ github.workspace }}/secret.key
         run: cd bin/dither && bundle exec ruby dither.rb >> dither.log 2>&1 &
 
+      - name: Install ImageMagick
+        run: |
+          sudo apt update
+          sudo apt install imagemagick
+
       - name: Test build
         env:
           DITHER_SERVER: http://localhost:4567