diff --git a/.github/workflows/checks.yml b/.github/workflows/checks.yml
index 803f7e5..16b2356 100644
--- a/.github/workflows/checks.yml
+++ b/.github/workflows/checks.yml
@@ -13,9 +13,7 @@ jobs:
       - name: Check out code
         uses: actions/checkout@v2
       - name: Lint checks
-        uses: hadolint/hadolint-action@v1.6.0
-        with:
-          dockerfile: Dockerfile
+        uses: hadolint/hadolint-action@v2.1.0
 
   build:
     name: docker build
diff --git a/Dockerfile b/Dockerfile
index 8140846..a9b115e 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -31,48 +31,31 @@ ENV LANG en_US.UTF-8
 
 RUN apt-get update && \
     apt-get install --no-install-recommends -y \
-        apt-utils=2.0.6 \
+        apt-utils=2.0.8 \
         build-essential=12.8ubuntu1.1 \
         bzip2=1.0.8-2 \
-        curl=7.68.0-1ubuntu2.7 \
-        git=1:2.25.1-1ubuntu3.2 \
+        curl=7.68.0-1ubuntu2.11 \
+        git=1:2.25.1-1ubuntu3.4 \
         html2text=1.3.2a-25 \
-        libc6-i386=2.31-0ubuntu9.2 \
+        libc6-i386=2.31-0ubuntu9.9 \
         lib32stdc++6=10.3.0-1ubuntu1~20.04 \
         lib32gcc1=1:10.3.0-1ubuntu1~20.04 \
         lib32ncurses6=6.2-0ubuntu2 \
-        lib32z1=1:1.2.11.dfsg-2ubuntu1.2 \
+        lib32z1=1:1.2.11.dfsg-2ubuntu1.3 \
         locales=2.31-0ubuntu9 \
-        openjdk-11-jdk=11.0.13+8-0ubuntu1~20.04 \
-        qemu-kvm=1:4.2-3ubuntu6.19 \
+        openjdk-11-jdk=11.0.15+10-0ubuntu0.20.04.1 \
+        qemu-kvm=1:4.2-3ubuntu6.21 \
         unzip=6.0-25ubuntu1 \
     && rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/* \
     && localedef -i en_US -c -f UTF-8 -A /usr/share/locale/locale.alias en_US.UTF-8
 
-RUN locale-gen
+RUN locale-gen && rm -f /var/lib/dpkg/info/ca-certificates-java.postinst configure
 
-RUN rm -f /var/lib/dpkg/info/ca-certificates-java.postinst configure
-
-RUN curl -s https://dl.google.com/android/repository/commandlinetools-linux-${VERSION_TOOLS}_latest.zip > /tools.zip && \
-    unzip /tools.zip -d ${ANDROID_HOME} && \
-    rm -v /tools.zip
-
-RUN mkdir -p ${ANDROID_HOME}/licenses/ && \
-    printf "8933bad161af4178b1185d1a37fbf41ea5269c55\\nd56f5187479451eabf01fb78af6dfcb131a6481e\\n24333f8a63b6825ea9c5514f83c2829b004d1fee" > ${ANDROID_HOME}/licenses/android-sdk-license && \
-    printf "84831b9409646a918e30573bab4c9c91346d8abd\\n504667f4c0de7af1a06de9f4b1727b84351f2910" > ${ANDROID_HOME}/licenses/android-sdk-preview-license
-
-RUN yes | ${ANDROID_TOOLS}/bin/sdkmanager --sdk_root=${ANDROID_HOME} --licenses
-
-RUN mkdir -p /root/.android && \
-    touch /root/.android/repositories.cfg && \
-    ${ANDROID_TOOLS}/bin/sdkmanager --sdk_root=${ANDROID_HOME} --update
+RUN mkdir -p ${ANDROID_HOME} && chmod +070 ${ANDROID_HOME}
 
 COPY packages.txt ${ANDROID_HOME}
-RUN while read -r package; do PACKAGES="${PACKAGES}${package} "; done < /sdk/packages.txt && \
-    ${ANDROID_TOOLS}/bin/sdkmanager --sdk_root=${ANDROID_HOME} ${PACKAGES}
-
 COPY utils ${ANDROID_HOME}/utils
 
-RUN chmod +070 ${ANDROID_HOME}
+RUN ${ANDROID_HOME}/utils/install-android-sdk.sh
 
 WORKDIR /work
diff --git a/utils/install-android-sdk.sh b/utils/install-android-sdk.sh
new file mode 100755
index 0000000..cd56a63
--- /dev/null
+++ b/utils/install-android-sdk.sh
@@ -0,0 +1,17 @@
+curl -s https://dl.google.com/android/repository/commandlinetools-linux-${VERSION_TOOLS}_latest.zip > /tools.zip && \
+unzip /tools.zip -d ${ANDROID_HOME} && \
+rm -v /tools.zip
+
+mkdir -p ${ANDROID_HOME}/licenses/ && \
+printf "8933bad161af4178b1185d1a37fbf41ea5269c55\\nd56f5187479451eabf01fb78af6dfcb131a6481e\\n24333f8a63b6825ea9c5514f83c2829b004d1fee" > ${ANDROID_HOME}/licenses/android-sdk-license && \
+printf "84831b9409646a918e30573bab4c9c91346d8abd\\n504667f4c0de7af1a06de9f4b1727b84351f2910" > ${ANDROID_HOME}/licenses/android-sdk-preview-license
+
+yes | ${ANDROID_TOOLS}/bin/sdkmanager --sdk_root=${ANDROID_HOME} --licenses
+
+mkdir -p /root/.android && \
+touch /root/.android/repositories.cfg && \
+${ANDROID_TOOLS}/bin/sdkmanager --sdk_root=${ANDROID_HOME} --update
+
+while read -r package; do PACKAGES="${PACKAGES}${package} "; done < /sdk/packages.txt && \
+${ANDROID_TOOLS}/bin/sdkmanager --sdk_root=${ANDROID_HOME} ${PACKAGES}
+