diff --git a/.github/workflows/build-action.yml b/.github/workflows/build-action.yml
new file mode 100644
index 000000000..416779217
--- /dev/null
+++ b/.github/workflows/build-action.yml
@@ -0,0 +1,84 @@
+name: Build Image
+
+# Trigger the workflow on push or pull request
+on:
+  push:
+    paths:
+      - '**.bash'
+      - '**.sh'
+      - '!test.bash'
+  pull_request:
+    paths:
+      - '**.bash'
+      - '**.sh'
+      - '!test.bash'
+
+jobs:
+  build32:
+    # Using latest Ubuntu (not the GitHub Actions default) to get latest tool versions in GitHub Actions environment
+    runs-on: ubuntu-20.04
+
+    steps:
+       - name: Checkout repository
+         uses: actions/checkout@v2
+       - name: Environment variables
+         run: sudo -E bash -c set
+       - name: Install required packages
+         run: sudo apt-get install git wget unzip libarchive-zip-perl dos2unix xz-utils kpartx
+       - name: Cache Raspberry Pi OS image
+         id: cache-rasios32-image
+         uses: actions/cache@v2
+         env:
+          cache-name: cache-rasios32-image
+         with:
+           path: raspios_lite_armhf_latest.zip
+           key: ${{ runner.os }}-build-${{ env.cache-name }}-${{ hashFiles('raspios_lite_armhf_latest.zip') }}
+       - name: Download Raspberry Pi OS image
+         if: steps.cache-rasios32-image.outputs.cache-hit != 'true'
+         run: wget -qO raspios_lite_armhf_latest.zip https://downloads.raspberrypi.org/raspios_lite_armhf_latest
+       - name: Run build.bash rpi
+         run: sudo -E ./build.bash rpi
+       - name: getfilename
+         id: getfilename
+         run: echo "::set-output name=file::$(ls openhabian-*.img)"
+       - name: Archive
+         uses: actions/upload-artifact@v2
+         with:
+           # Artifact name
+           name: ${{ steps.getfilename.outputs.file }}
+           # Directory containing files to upload
+           path: ${{ steps.getfilename.outputs.file }}
+  build64experimental:
+    # Using latest Ubuntu (not the GitHub Actions default) to get latest tool versions in GitHub Actions environment
+    runs-on: ubuntu-20.04
+
+    steps:
+       - name: Checkout repository
+         uses: actions/checkout@v2
+       - name: Environment variables
+         run: sudo -E bash -c set
+       - name: Install required packages
+         run: sudo apt-get install git wget unzip libarchive-zip-perl dos2unix xz-utils kpartx
+       - name: Cache Raspberry Pi OS image
+         id: cache-rasios64-image
+         uses: actions/cache@v2
+         env:
+          cache-name: cache-rasios64-image
+         with:
+           path: raspios_lite_arm64_latest.zip
+           key: ${{ runner.os }}-build-${{ env.cache-name }}-${{ hashFiles('raspios_lite_arm64_latest.zip') }}
+       - name: Download Raspberry Pi OS image
+         if: steps.cache-rasios64-image.outputs.cache-hit != 'true'
+         run: wget -qO raspios_lite_arm64_latest.zip https://downloads.raspberrypi.org/raspios_arm64_latest
+       - name: Run build.bash rpi64
+         run: sudo -E ./build.bash rpi64
+       - name: getfilename
+         id: getfilename
+         run: echo "::set-output name=file::$(ls openhabian-*.img)"
+       - name: Archive
+         uses: actions/upload-artifact@v2
+         with:
+           # Artifact name
+           name: ${{ steps.getfilename.outputs.file }}
+           # Directory containing files to upload
+           path: ${{ steps.getfilename.outputs.file }}
diff --git a/.github/workflows/shellcheck-action.yml b/.github/workflows/shellcheck-action.yml
index 22db20e20..7af089cbb 100644
--- a/.github/workflows/shellcheck-action.yml
+++ b/.github/workflows/shellcheck-action.yml
@@ -1,17 +1,22 @@
-# This is a basic workflow to help you get started with Actions
+name: ShellCheck
 
-name: shellcheck
-
-# Controls when the action will run. Triggers the workflow on push or pull request
-# events but only for the master branch
+# Trigger the workflow on push or pull request
 on:
-  push
-# A workflow run is made up of one or more jobs that can run sequentially or in parallel
+  push:
+    paths:
+      - '**.bash'
+      - '**.sh'
+      - '!test.bash'
+  pull_request:
+    paths:
+      - '**.bash'
+      - '**.sh'
+      - '!test.bash'
+
 jobs:
-  # This workflow contains a single job called "build"
-  build:
-    # The type of runner that the job will run on
-    runs-on: ubuntu-latest
+  shellcheck:
+    # Using latest Ubuntu (not the GitHub Actions default) to get latest tool versions in GitHub Actions environment
+    runs-on: ubuntu-20.04
 
     steps:
        - name: Checkout repository
@@ -20,12 +25,23 @@ jobs:
          run: sudo -E bash -c set
        - name: Install required packages
          run: sudo apt-get install shellcheck
-       - name: "Check 1"
-         run: shellcheck -x -s bash openhabian-setup.sh && echo "shellcheck openhabian-setup.sh - OK";
-       - name: "Check 2"
-         run: shellcheck -x -s bash functions/*.bash && echo "shellcheck functions/*.bash - OK";
-       - name: "Check 3"
-         run: shellcheck -x -s bash build-image/*.bash && echo "shellcheck build-image/*.bash - OK";
-       - name: "Check 4"
-         run: shellcheck -x -s bash build.bash && echo "shellcheck build.bash - OK"
-
+       - name: "ShellCheck openhabian-setup.sh"
+         run: |
+           echo "ShellCheck openhabian-setup.sh..."
+           if shellcheck -x -s bash openhabian-setup.sh; then echo "OK"; else echo "FAILED"; exit 1; fi
+         shell: bash
+       - name: "ShellCheck functions/*.bash"
+         run: |
+           echo "ShellCheck functions/*.bash..."
+           if shellcheck -x -s bash functions/*.bash; then echo "OK"; else echo "FAILED"; exit 1; fi
+         shell: bash
+       - name: "ShellCheck build-image/*.bash"
+         run: |
+           echo "ShellCheck build-image/*.bash..."
+           if shellcheck -x -s bash build-image/*.bash; then echo "OK"; else echo "FAILED"; exit 1; fi
+         shell: bash
+       - name: "ShellCheck build.bash"
+         run: |
+           echo "ShellCheck build.bash..."
+           if shellcheck -x -s bash build.bash; then echo "OK"; else echo "FAILED"; exit 1; fi
+         shell: bash
diff --git a/.travis.yml b/.travis.yml
index 33f8f0ef2..c3507f88b 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,16 +1,10 @@
 language: shell
 os: linux
-# using latest Ubuntu (not the travis-ci default) to get latest tool versions in Travis environment
+# Using latest Ubuntu (not the Travis-CI default) to get latest tool versions in Travis environment
 dist: focal
 
 cache: false
 
-addons:
-  apt:
-    packages:
-    - shellcheck
-    update: true
-
 git:
   submodules: false
   quiet: true
@@ -19,7 +13,7 @@ services:
   - docker
 
 stages:
-  - BATS and ShellCheck tests
+  - BATS tests
   - openHABian installation tests
 
 install:
@@ -28,10 +22,10 @@ install:
 jobs:
   fast_finish: true
   allow_failures:
-    - stage: BATS and ShellCheck tests
+    - stage: BATS tests
   include:
-    - stage: BATS and ShellCheck tests
-      name: BATS and ShellCheck tests on virtual RPi4
+    - stage: BATS tests
+      name: BATS tests on virtual RPi4
       env: HW=rpi4
       arch: arm64
       script:
@@ -42,14 +36,13 @@ jobs:
         - docker run --name "unit-tests" -i openhabian/bats-openhabian bash -c 'bats --tap --recursive --filter "unit-." .'
         - docker run --name "installation-tests" -i openhabian/bats-openhabian bash -c 'bats --tap --recursive --filter "installation-." .'
         - docker run --name "destructive-tests" -i openhabian/bats-openhabian bash -c 'bats --tap --recursive --filter "destructive-." .'
-        - shellcheck -x -s bash openhabian-setup.sh functions/*.bash build-image/*.bash build.bash && echo "shellcheck - OK"
     - stage: openHABian installation tests
       name: openHABian installation test with 64bit Azul Java 8 on native amd64
       env: HW=amd64
       arch: amd64
       script:
         # 64bit Azul Java 8 on a 64bit amd64 virtual platform, running in a 64bit OS on Travis AMD64 HW
-        - sed -i 's/^java_opt=.*$/java_opt=Zulu8-64/' build-image/openhabian.conf
+        - sed -i 's|^java_opt=.*$|java_opt=Zulu8-64|' build-image/openhabian.conf
         - docker build -t openhabian/${HW}-openhabian -f Dockerfile.amd64 .
         - echo -e "\n\e[36mopenHABian test installation using 64bit Azul Enterprise Java 8 running on a\e[31m 64bit OS\e[36m running on native ${HW}...\e[0m\n"
         - docker run --name "openhabian-${HW}" -d openhabian/${HW}-openhabian;
@@ -59,7 +52,7 @@ jobs:
       arch: amd64
       script:
         # 64bit Azul Java 11 on a 64bit amd64 virtual platform, running in a 64bit => Ubuntu <= OS on Travis AMD64 HW
-        - sed -i 's/^java_opt=.*$/java_opt=Zulu11-64/' build-image/openhabian.conf
+        - sed -i 's|^java_opt=.*$|java_opt=Zulu11-64|' build-image/openhabian.conf
         - docker build -t openhabian/${HW}-openhabian -f Dockerfile.amd64-ubuntu .
         - echo -e "\n\e[36mopenHABian test installation using 64bit Azul Enterprise Java 11 running on a\e[31m 64bit Ubuntu\e[36m running on native ${HW}...\e[0m\n"
         - docker run --name "openhabian-${HW}" -d openhabian/${HW}-openhabian;
@@ -69,7 +62,7 @@ jobs:
       arch: arm64
       script:
         # 32bit Azul Java 8 on a 32bit ARMv7l (RPi2) virtual platform, running in a 32bit OS on Travis Arm64 HW
-        - sed -i 's/^java_opt=.*$/java_opt=Zulu8-32/' build-image/openhabian.conf
+        - sed -i 's|^java_opt=.*$|java_opt=Zulu8-32|' build-image/openhabian.conf
         - docker build -t openhabian/${HW}-openhabian -f Dockerfile.raspberry-pi2 .
         - echo -e "\n\e[36mopenHABian test installation using 32bit Azul Embedded Java 8 running on a\e[31m 32bit OS\e[36m running in a virtual ${HW}...\e[0m\n"
         - docker run --memory="1g" --memory-reservation="1g" --name "openhabian-${HW}" -d openhabian/${HW}-openhabian
@@ -79,7 +72,7 @@ jobs:
       arch: arm64
       script:
         # 32bit Azul Java 11 on a 64bit ARMv8 (RPi3) virtual platform, running in a 32bit OS on Travis Arm64 HW
-        - sed -i 's/^java_opt=.*$/java_opt=Zulu11-32/' build-image/openhabian.conf
+        - sed -i 's|^java_opt=.*$|java_opt=Zulu11-32|' build-image/openhabian.conf
         - docker build -t openhabian/${HW}-openhabian -f Dockerfile.raspberrypi3 .
         - echo -e "\n\e[36mopenHABian test installation using 32bit Azul Embedded Java 11 running on a\e[31m 32bit OS\e[36m running in a virtual ${HW}...\e[0m\n"
         - docker run --memory="1g" --memory-reservation="1g" --name "openhabian-${HW}" -d openhabian/${HW}-openhabian;
@@ -89,7 +82,7 @@ jobs:
       arch: arm64
       script:
         # 64bit Azul Java 8 on a 64bit ARMv8 (RPi3) virtual platform, running in a 64bit OS on Travis Arm64 HW
-        - sed -i 's/^java_opt=.*$/java_opt=Zulu8-64/' build-image/openhabian.conf
+        - sed -i 's|^java_opt=.*$|java_opt=Zulu8-64|' build-image/openhabian.conf
         - docker build -t openhabian/${HW}-openhabian -f Dockerfile.raspberrypi3-64 .
         - echo -e "\n\e[36mopenHABian test installation using 64bit Azul Embedded Java 8 running on a\e[31m 64bit OS\e[36m running in a virtual ${HW}...\e[0m\n"
         - docker run --memory="2g" --memory-reservation="2g" --name "openhabian-${HW}" -d openhabian/${HW}-openhabian;
@@ -99,7 +92,7 @@ jobs:
       arch: arm64
       script:
         # AdoptOpenJDK Java 11 on a 32bit ARMv7l (RPi2) virtual platform, running in a 32bit OS on Travis Arm64 HW
-        - sed -i 's/^java_opt=.*$/java_opt=Adopt11/' build-image/openhabian.conf
+        - sed -i 's|^java_opt=.*$|java_opt=Adopt11|' build-image/openhabian.conf
         - docker build -t openhabian/${HW}-openhabian -f Dockerfile.raspberry-pi2 .
         - echo -e "\n\e[36mopenHABian test installation using AdoptOpenJDK Java 11 running on a\e[31m 32bit OS\e[36m running in a virtual ${HW}...\e[0m\n"
         - docker run --memory="1g" --memory-reservation="1g" --name "openhabian-${HW}" -d openhabian/${HW}-openhabian;
diff --git a/Dockerfile.amd64-ubuntu b/Dockerfile.amd64-ubuntu
index 2d92a7656..c88fa40fc 100644
--- a/Dockerfile.amd64-ubuntu
+++ b/Dockerfile.amd64-ubuntu
@@ -1,4 +1,4 @@
-FROM balenalib/intel-nuc-ubuntu:focal-build
+FROM balenalib/amd64-ubuntu:focal-build
 
 
 ENV container docker
diff --git a/build.bash b/build.bash
index 0900f686f..b539e3019 100755
--- a/build.bash
+++ b/build.bash
@@ -212,7 +212,7 @@ mkdir $buildfolder
 if [ "$hw_platform" == "pi-raspios32" ] || [ "$hw_platform" == "pi-raspios64beta" ]; then
   if [ "$hw_platform" == "pi-raspios64beta" ]; then
     zipfile=raspios_lite_arm64_latest.zip
-    baseurl="https://downloads.raspberrypi.org/raspios_arm64/images/raspios_arm64-2020-05-28/2020-05-27-raspios-buster-arm64.zip"
+    baseurl="https://downloads.raspberrypi.org/raspios_arm64_latest"
     bits=64
   else
     zipfile=raspios_lite_armhf_latest.zip
@@ -245,7 +245,8 @@ if [ "$hw_platform" == "pi-raspios32" ] || [ "$hw_platform" == "pi-raspios64beta
     cp $zipfile "$buildfolder/$zipfile"
   else
     echo_process "Downloading latest Raspberry Pi OS ($bits-bit) Lite image (no local copy of $zipfile found)... "
-    wget -nv -O "$buildfolder/$zipfile" "$baseurl"
+    wget -qO "$zipfile" "$baseurl"
+    cp $zipfile "$buildfolder/$zipfile"
   fi
   echo_process "Unpacking image... "
   unzip $buildfolder/$zipfile -d $buildfolder
@@ -265,13 +266,10 @@ if [ "$hw_platform" == "pi-raspios32" ] || [ "$hw_platform" == "pi-raspios64beta
   ln -s $buildfolder/root/etc/systemd/system/openhabian-installer.service $buildfolder/root/etc/systemd/system/multi-user.target.wants/openhabian-installer.service
 
   echo_process "Setting default runlevel multiuser.target... "
-  ( # open a subshell, returns to current dir automatically
-    cd $buildfolder/root/etc/systemd/system/ || exit 1
-    rm -rf default.target
-    ln -s ../../../lib/systemd/system/multi-user.target default.target
-    # disable autologin
-    rm -f $buildfolder/root/etc/systemd/system/getty@tty1.service.d/autologin.conf
-  )
+  rm -rf $buildfolder/root/etc/systemd/system/default.target
+  ln -s $buildfolder/lib/systemd/system/multi-user.target default.target
+  # disable autologin
+  rm -f $buildfolder/root/etc/systemd/system/getty@tty1.service.d/autologin.conf
 
   touch $buildfolder/root/opt/openHABian-install-inprogress
   # maybe we should use a trap to get this done in case of error
@@ -281,7 +279,8 @@ if [ "$hw_platform" == "pi-raspios32" ] || [ "$hw_platform" == "pi-raspios64beta
   mount_image_file_boot "$imagefile" "$buildfolder"
   touch $buildfolder/boot/ssh
   cp $sourcefolder/first-boot.bash $buildfolder/boot/first-boot.bash
-  sed -i -e '1r functions/helpers.bash' $buildfolder/boot/first-boot.bash # Add platform identification
+  cp $sourcefolder/../functions/helpers.bash $buildfolder/boot/helpers.bash
+  cp $sourcefolder/../functions/openhabian.bash $buildfolder/boot/openhabian.bash
   touch $buildfolder/boot/first-boot.log
   unix2dos -n $sourcefolder/openhabian.$hw_platform.conf $buildfolder/boot/openhabian.conf
   cp $sourcefolder/webif.bash $buildfolder/boot/webif.bash
@@ -304,11 +303,13 @@ destination="openhabian-$hw_platform-$timestamp-git$file_tag$shorthash-crc$crc32
 mv -v $imagefile "$destination"
 rm -rf $buildfolder
 
-echo_process "Compressing image... "
-# speedup compression, T0 will use all cores and should be supported by reasonably new versions of xz
-xz --verbose --compress --keep -T0 "$destination"
-crc32checksum=$(crc32 "$destination.xz")
-mv "$destination.xz" "openhabian-$hw_platform-$timestamp-git$file_tag$shorthash-crc$crc32checksum.img.xz"
+if ! running_in_docker && ! running_on_github; then
+  echo_process "Compressing image... "
+  # speedup compression, T0 will use all cores and should be supported by reasonably new versions of xz
+  xz --verbose --compress --keep -T0 "$destination"
+  crc32checksum=$(crc32 "$destination.xz")
+  mv "$destination.xz" "openhabian-$hw_platform-$timestamp-git$file_tag$shorthash-crc$crc32checksum.img.xz"
+fi
 
 echo_process "Finished! The results:"
 ls -alh "openhabian-$hw_platform-$timestamp"*
diff --git a/functions/helpers.bats b/functions/helpers.bats
index 15f22a54d..1d2e00870 100644
--- a/functions/helpers.bats
+++ b/functions/helpers.bats
@@ -2,30 +2,6 @@
 
 load helpers.bash
 
-testNonExistingHost() {
-  tryUntil "ping -c 1 $1" 10 1
-}
-
-testAppearingHost() {
-  ( sleep 3; echo "127.0.0.1  $1" >> /etc/hosts ) &
-
-  tryUntil "ping -c 1 $1" 10 1
-}
-
-@test "unit-tryExistingSite" {
-  run testAppearingHost thiswillappear
-  [ "$status" -eq 7 ]
-
-  echo -e "# ${COL_GREEN}$(timestamp) [openHABian] Ping to host appearing after 3 seconds succeeded.${COL_DEF}" >&3
-}
-
-@test "unit-tryNonExistingSite" {
-  run testNonExistingHost nothisdoesnotexit
-  [ "$status" -eq 0 ]
-
-  echo -e "# ${COL_GREEN}$(timestamp) [openHABian] Pinging to nonexistingsite failed (correctly so).${COL_DEF}" >&3
-}
-
 @test "unit-cond_echo" {
   run cond_echo 'Generic Text @!/\1'
   [ "$status" -eq 0 ]