diff --git a/.github/workflows/image.yml b/.github/workflows/image.yml
index 11c42ba..86b51bd 100644
--- a/.github/workflows/image.yml
+++ b/.github/workflows/image.yml
@@ -4,20 +4,28 @@ on:
   push:
     branches:
       - main
+  pull_request:
 
 jobs:
   build:
     runs-on: ubuntu-latest
+    container:
+      image: archlinux:base-devel
+      options: --privileged
+    strategy:
+      matrix:
+        platform: [odroid, rpi3, rpi4]
     steps:
       - uses: actions/checkout@v2
+      - run: echo -e "[aurto]\nSigLevel = Optional\nServer = https://aur.raccube.net/" >> /etc/pacman.conf
       - name: Install dependencies
-        run: sudo apt install -y libarchive-tools curl fdisk qemu-user-static zstd
+        run: pacman -Syu --noconfirm gptfdisk arch-install-scripts git qemu-user-static-bin archlinuxarm-keyring python dosfstools
       - name: Build ODroid image
-        run: sudo ./build.sh odroid.img
+        run: sudo ./build.py ${{ matrix.platform }} robot-${{ matrix.platform }}.img
       - name: Compress image
-        run: zstd odroid.img
+        run: zstd robot-${{ matrix.platform }}.img
       - name: Publish compressed image
         uses: actions/upload-artifact@v2
         with:
-          name: ODroid Image
-          path: odroid.img.zst
+          name: ${{ matrix.platform }}
+          path: robot-${{ matrix.platform }}.img.zst
diff --git a/README.md b/README.md
index 8fc4c7c..cda3185 100644
--- a/README.md
+++ b/README.md
@@ -17,7 +17,6 @@ Scripts used to create a system image for SR brain board SD cards.
 
 - bash
 - Python 3.8 or newer
-- curl
 - fdisk
 - [arch-install-scripts](https://archlinux.org/packages/extra/any/arch-install-scripts/)
 - [archlinuxarm-keyring](http://mirror.archlinuxarm.org/armv6h/core/archlinuxarm-keyring-20140119-1-any.pkg.tar.xz)
diff --git a/build.py b/build.py
index 890f654..1250b1e 100755
--- a/build.py
+++ b/build.py
@@ -112,6 +112,7 @@ def run_stage(stage: Path, environment, build_dir):
 
     print("SR Image Builder")
     print(f"Build directory: {args.build_dir}")
+    Path(args.build_dir).mkdir(parents=True, exist_ok=True)
 
     stages = determine_stage_list()
 
@@ -127,6 +128,7 @@ def run_stage(stage: Path, environment, build_dir):
         "CACHE_DIR": str(args.cache_dir),
         "PLATFORM": args.platform,
     }
+    # TODO: Pass through GITHUB_* environment variables
 
     atexit.register(cleanup, args.build_dir)
 
diff --git a/stage0/00-host_setup-disk.sh b/stage0/00-host_setup-disk.sh
index 2e0ece6..850e27b 100755
--- a/stage0/00-host_setup-disk.sh
+++ b/stage0/00-host_setup-disk.sh
@@ -1,5 +1,6 @@
 #!/bin/bash
 set -e
+set -x
 
 source ./util.sh
 
@@ -34,25 +35,34 @@ info "Partitioning disk image"
   echo        # last sector (accept default)
 
   echo w # write changes
-) | /sbin/fdisk "$IMAGE_OUTPUT_PATH" > /dev/null
+) | /sbin/fdisk "$IMAGE_OUTPUT_PATH" #> /dev/null
 
 if [[ "$OUTPUT_DEVICE" =~ ^/dev/loop ]]; then
   info "Setting up loop device"
-  losetup -P "$OUTPUT_DEVICE" "$IMAGE_OUTPUT_PATH"
-  boot_part="${OUTPUT_DEVICE}p1"
-  root_part="${OUTPUT_DEVICE}p2"
+
+  mkdir -p "$BUILD_DIR"
+  mount -t ext4 -o loop,offset=413696 "$IMAGE_OUTPUT_PATH" "$BUILD_DIR"
+  mkdir -p "$BUILD_DIR/boot"
+  mount -t vfat -o loop,offset=4096 "$IMAGE_OUTPUT_PATH" "$BUILD_DIR/boot"
 else
   boot_part="${OUTPUT_DEVICE}1"
   root_part="${OUTPUT_DEVICE}2"
 fi
 
+/sbin/fdisk -l "$IMAGE_OUTPUT_PATH"
+file "$IMAGE_OUTPUT_PATH"
+losetup
+file "$OUTPUT_DEVICE"
+file "$boot_part"
+file "$root_part"
+ls -lRa /dev/
+
 info "Creating boot filesystem"
 mkfs.vfat -F 32 "$boot_part"
 
 info "Creating root filesystem"
 mkfs.ext4 -q "$root_part"
 
-mkdir -p "$BUILD_DIR"
 
 info "Mounting root partition"
 mount -t ext4 -o rw,defaults,noatime "$root_part" "$BUILD_DIR"