diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index 749e802..bf751ea 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -17,7 +17,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        version: [8-jdk-jammy, 11-jdk-jammy, 11-jdk-alpine, 17-jdk-jammy, 17-jdk-alpine]
+        version: [8-jdk-jammy, 11-jdk-jammy, 11-jdk-alpine, 17-jdk-jammy, 17-jdk-alpine, 21-jdk-jammy, 21-jdk-alpine]
     steps:
       - name: checkout
         uses: actions/checkout@v2
diff --git a/README.md b/README.md
index cfafabf..ac274a7 100644
--- a/README.md
+++ b/README.md
@@ -4,7 +4,11 @@
 
 * [jdk8](https://github.com/groovy/docker-groovy/blob/master/jdk8/Dockerfile)
 * [jdk11](https://github.com/groovy/docker-groovy/blob/master/jdk11/Dockerfile)
-* [jdk17, latest](https://github.com/groovy/docker-groovy/blob/master/jdk17/Dockerfile)
+* [jdk11-alpine](https://github.com/groovy/docker-groovy/blob/master/jdk11-alpine/Dockerfile)
+* [jdk17](https://github.com/groovy/docker-groovy/blob/master/jdk17/Dockerfile)
+* [jdk17-alpine](https://github.com/groovy/docker-groovy/blob/master/jdk17-alpine/Dockerfile)
+* [jdk21, latest](https://github.com/groovy/docker-groovy/blob/master/jdk21/Dockerfile)
+* [jdk21-alpine](https://github.com/groovy/docker-groovy/blob/master/jdk21-alpine/Dockerfile)
 
 ## What is Groovy?
 
diff --git a/jdk21-alpine/Dockerfile b/jdk21-alpine/Dockerfile
new file mode 100644
index 0000000..38f3447
--- /dev/null
+++ b/jdk21-alpine/Dockerfile
@@ -0,0 +1,68 @@
+FROM eclipse-temurin:21-jdk-alpine
+
+CMD ["groovysh"]
+
+ENV GROOVY_HOME /opt/groovy
+
+RUN set -o errexit -o nounset \
+    && echo "Adding groovy user and group" \
+    && addgroup --system --gid 1000 groovy \
+    && adduser --system --ingroup groovy --uid 1000 --shell /bin/ash groovy \
+    && mkdir --parents /home/groovy/.groovy/grapes \
+    && chown -R groovy:groovy /home/groovy \
+    && chmod -R 1777 /home/groovy \
+    \
+    && echo "Symlinking root .groovy to groovy .groovy" \
+    && ln -s /home/groovy/.groovy /root/.groovy
+
+VOLUME /home/groovy/.groovy/grapes
+
+WORKDIR /home/groovy
+
+ENV GROOVY_VERSION 4.0.15
+RUN set -o errexit -o nounset \
+    && echo "Installing build dependencies" \
+    && apk add --no-cache --virtual .build-deps \
+        gnupg \
+    \
+    && echo "Downloading Groovy" \
+    && wget --no-verbose --output-document=groovy.zip "https://archive.apache.org/dist/groovy/${GROOVY_VERSION}/distribution/apache-groovy-binary-${GROOVY_VERSION}.zip" \
+    \
+    && echo "Importing keys listed in http://www.apache.org/dist/groovy/KEYS from key server" \
+    && export GNUPGHOME="$(mktemp -d)" \
+    && gpg --batch --no-tty --keyserver keyserver.ubuntu.com --recv-keys \
+        7FAA0F2206DE228F0DB01AD741321490758AAD6F \
+        331224E1D7BE883D16E8A685825C06C827AF6B66 \
+        34441E504A937F43EB0DAEF96A65176A0FB1CD0B \
+        9A810E3B766E089FFB27C70F11B595CEDC4AEBB5 \
+        81CABC23EECA0790E8989B361FF96E10F0E13706 \
+    \
+    && echo "Checking download signature" \
+    && wget --no-verbose --output-document=groovy.zip.asc "https://archive.apache.org/dist/groovy/${GROOVY_VERSION}/distribution/apache-groovy-binary-${GROOVY_VERSION}.zip.asc" \
+    && gpg --batch --no-tty --verify groovy.zip.asc groovy.zip \
+    && rm -rf "${GNUPGHOME}" \
+    && rm groovy.zip.asc \
+    \
+    && echo "Cleaning up build dependencies" \
+    && apk del .build-deps \
+    \
+    && echo "Installing Groovy" \
+    && unzip groovy.zip \
+    && rm groovy.zip \
+    && mv "groovy-${GROOVY_VERSION}" "${GROOVY_HOME}/" \
+    && ln -s "${GROOVY_HOME}/bin/grape" /usr/bin/grape \
+    && ln -s "${GROOVY_HOME}/bin/groovy" /usr/bin/groovy \
+    && ln -s "${GROOVY_HOME}/bin/groovyc" /usr/bin/groovyc \
+    && ln -s "${GROOVY_HOME}/bin/groovyConsole" /usr/bin/groovyConsole \
+    && ln -s "${GROOVY_HOME}/bin/groovydoc" /usr/bin/groovydoc \
+    && ln -s "${GROOVY_HOME}/bin/groovysh" /usr/bin/groovysh \
+    && ln -s "${GROOVY_HOME}/bin/java2groovy" /usr/bin/java2groovy \
+    \
+    && echo "Editing startGroovy to include java.xml.bind module" \
+    && sed --in-place 's|startGroovy ( ) {|startGroovy ( ) {\n    JAVA_OPTS="$JAVA_OPTS --add-modules=ALL-SYSTEM"|' "${GROOVY_HOME}/bin/startGroovy"
+
+USER 1000:1000
+
+RUN set -o errexit -o nounset \
+    && echo "Testing Groovy installation" \
+    && groovy --version
diff --git a/jdk21/Dockerfile b/jdk21/Dockerfile
new file mode 100644
index 0000000..23e4212
--- /dev/null
+++ b/jdk21/Dockerfile
@@ -0,0 +1,70 @@
+FROM eclipse-temurin:21-jdk-jammy
+
+CMD ["groovysh"]
+
+ENV GROOVY_HOME /opt/groovy
+
+RUN set -o errexit -o nounset \
+    && echo "Adding groovy user and group" \
+    && groupadd --system --gid 1000 groovy \
+    && useradd --system --gid groovy --uid 1000 --shell /bin/bash --create-home groovy \
+    && mkdir --parents /home/groovy/.groovy/grapes \
+    && chown --recursive groovy:groovy /home/groovy \
+    && chmod --recursive 1777 /home/groovy \
+    \
+    && echo "Symlinking root .groovy to groovy .groovy" \
+    && ln --symbolic /home/groovy/.groovy /root/.groovy
+
+VOLUME /home/groovy/.groovy/grapes
+
+WORKDIR /home/groovy
+
+RUN apt-get update \
+    && echo "Installing build dependencies" \
+    && apt-get install --yes --no-install-recommends \
+        dirmngr \
+        gnupg \
+        unzip \
+        wget \
+    && rm --recursive --force /var/lib/apt/lists/*
+
+ENV GROOVY_VERSION 4.0.15
+RUN set -o errexit -o nounset \
+    && echo "Downloading Groovy" \
+    && wget --no-verbose --output-document=groovy.zip "https://archive.apache.org/dist/groovy/${GROOVY_VERSION}/distribution/apache-groovy-binary-${GROOVY_VERSION}.zip" \
+    \
+    && echo "Importing keys listed in http://www.apache.org/dist/groovy/KEYS from key server" \
+    && export GNUPGHOME="$(mktemp -d)" \
+    && gpg --batch --no-tty --keyserver keyserver.ubuntu.com --recv-keys \
+        7FAA0F2206DE228F0DB01AD741321490758AAD6F \
+        331224E1D7BE883D16E8A685825C06C827AF6B66 \
+        34441E504A937F43EB0DAEF96A65176A0FB1CD0B \
+        9A810E3B766E089FFB27C70F11B595CEDC4AEBB5 \
+        81CABC23EECA0790E8989B361FF96E10F0E13706 \
+    \
+    && echo "Checking download signature" \
+    && wget --no-verbose --output-document=groovy.zip.asc "https://archive.apache.org/dist/groovy/${GROOVY_VERSION}/distribution/apache-groovy-binary-${GROOVY_VERSION}.zip.asc" \
+    && gpg --batch --no-tty --verify groovy.zip.asc groovy.zip \
+    && rm --recursive --force "${GNUPGHOME}" \
+    && rm groovy.zip.asc \
+    \
+    && echo "Installing Groovy" \
+    && unzip groovy.zip \
+    && rm groovy.zip \
+    && mv "groovy-${GROOVY_VERSION}" "${GROOVY_HOME}/" \
+    && ln --symbolic "${GROOVY_HOME}/bin/grape" /usr/bin/grape \
+    && ln --symbolic "${GROOVY_HOME}/bin/groovy" /usr/bin/groovy \
+    && ln --symbolic "${GROOVY_HOME}/bin/groovyc" /usr/bin/groovyc \
+    && ln --symbolic "${GROOVY_HOME}/bin/groovyConsole" /usr/bin/groovyConsole \
+    && ln --symbolic "${GROOVY_HOME}/bin/groovydoc" /usr/bin/groovydoc \
+    && ln --symbolic "${GROOVY_HOME}/bin/groovysh" /usr/bin/groovysh \
+    && ln --symbolic "${GROOVY_HOME}/bin/java2groovy" /usr/bin/java2groovy \
+    \
+    && echo "Editing startGroovy to include java.xml.bind module" \
+    && sed --in-place 's|startGroovy ( ) {|startGroovy ( ) {\n    JAVA_OPTS="$JAVA_OPTS --add-modules=ALL-SYSTEM"|' "${GROOVY_HOME}/bin/startGroovy"
+
+USER 1000:1000
+
+RUN set -o errexit -o nounset \
+    && echo "Testing Groovy installation" \
+    && groovy --version