diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
new file mode 100644
index 0000000..73cbf8a
--- /dev/null
+++ b/.github/workflows/build.yml
@@ -0,0 +1,20 @@
+name: CI
+on:
+  release:
+    types: [released, prereleased]
+  workflow_dispatch:  # allow manually running from the Actions tab
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    env:
+      BUILDX_PLATFORMS: linux/amd64,linux/arm64,linux/arm/v7
+    steps:
+      - uses: actions/checkout@v2
+      - uses: docker/setup-qemu-action@v1
+      - uses: docker/setup-buildx-action@v1
+      - uses: docker/login-action@v1
+        with:
+          username: ${{ secrets.DOCKERHUB_USERNAME }}
+          password: ${{ secrets.DOCKERHUB_PASSWORD }}
+      - run: bash build.sh --publish
diff --git a/build.sh b/build.sh
index 4ef712d..e7b4a79 100755
--- a/build.sh
+++ b/build.sh
@@ -3,10 +3,12 @@ set -e -o pipefail
 
 ./cp-static.sh
 tag=$(git describe --tags)
-echo "Building $tag"
+platforms=${BUILDX_PLATFORMS:-linux/amd64}
+alias buildx_build="docker buildx build --platform=${platforms}"
+echo "Building ${tag} for platforms ${platforms}"
 
-docker build --pull py3-baseimage -t "stevearc/pypicloud:latest" -t "stevearc/pypicloud:$tag"
-docker build --pull py3-alpine -t "stevearc/pypicloud:latest-alpine" -t "stevearc/pypicloud:$tag-alpine"
+buildx_build --pull py3-baseimage -t "stevearc/pypicloud:latest"
+buildx_build --pull py3-alpine -t "stevearc/pypicloud:latest-alpine"
 
 if [ "$1" == '--publish' ]; then
   if [ -n "$(git status --porcelain)" ]; then
@@ -19,11 +21,11 @@ if [ "$1" == '--publish' ]; then
   ./test.sh latest
   ./test.sh latest-alpine
   echo "Tests passed"
-  docker push "stevearc/pypicloud:latest"
-  docker push "stevearc/pypicloud:latest-alpine"
+  buildx_build --push py3-baseimage -t "stevearc/pypicloud:latest"
+  buildx_build --push py3-alpine -t "stevearc/pypicloud:latest-alpine"
   if git describe --tags --exact-match; then
-    docker push "stevearc/pypicloud:$tag"
-    docker push "stevearc/pypicloud:$tag-alpine"
+    buildx_build --push py3-baseimage -t "stevearc/pypicloud:$tag"
+    buildx_build --push py3-alpine -t "stevearc/pypicloud:$tag-alpine"
   else
     echo "Not pushing $tag because it is not an exact version"
   fi