diff --git a/tests/dockerfiles/php81/1_build.sh b/tests/dockerfiles/php81/1_build.sh
new file mode 100755
index 0000000..9c0fe70
--- /dev/null
+++ b/tests/dockerfiles/php81/1_build.sh
@@ -0,0 +1,3 @@
+# Build an image.
+set -x
+docker build --tag="php-curl-class/php81" .
diff --git a/tests/dockerfiles/php81/2_start.sh b/tests/dockerfiles/php81/2_start.sh
new file mode 100755
index 0000000..1eeea23
--- /dev/null
+++ b/tests/dockerfiles/php81/2_start.sh
@@ -0,0 +1,15 @@
+# Run image to create container.
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+set -x
+cd "${SCRIPT_DIR}/../../.."
+project_dir="${PWD}"
+
+docker start "php81" ||
+    docker run \
+        --detach \
+        --interactive \
+        --mount "type=bind,src=${project_dir},dst=/data,readonly=true" \
+        --name="php81" \
+        --tty \
+        "php-curl-class/php81"
diff --git a/tests/dockerfiles/php81/3_test.sh b/tests/dockerfiles/php81/3_test.sh
new file mode 100755
index 0000000..87f2d0b
--- /dev/null
+++ b/tests/dockerfiles/php81/3_test.sh
@@ -0,0 +1,17 @@
+# Run tests inside container.
+command=$(cat <<-END
+mkdir --parents "/tmp/php-curl-class" &&
+rsync --delete --exclude=".git" --exclude="vendor" --exclude="composer.lock" --links --recursive "/data/" "/tmp/php-curl-class/" &&
+cd "/tmp/php-curl-class" &&
+export CI_PHP_VERSION="8.1" &&
+(
+    [ ! -f "/tmp/.composer_updated" ] &&
+    composer --no-interaction update &&
+    touch "/tmp/.composer_updated" ||
+    exit 0
+) &&
+bash "tests/run.sh"
+END
+)
+set -x
+docker exec --tty "php81" sh -c "${command}"
diff --git a/tests/dockerfiles/php81/4_stop.sh b/tests/dockerfiles/php81/4_stop.sh
new file mode 100755
index 0000000..b1b8959
--- /dev/null
+++ b/tests/dockerfiles/php81/4_stop.sh
@@ -0,0 +1,3 @@
+# Stop container.
+set -x
+docker stop "php81"
diff --git a/tests/dockerfiles/php81/Dockerfile b/tests/dockerfiles/php81/Dockerfile
new file mode 100644
index 0000000..d6b4ed9
--- /dev/null
+++ b/tests/dockerfiles/php81/Dockerfile
@@ -0,0 +1,19 @@
+FROM php:8.1-cli
+ENV DEBIAN_FRONTEND noninteractive
+
+RUN apt-get --assume-yes --quiet update
+
+RUN apt-get --assume-yes --quiet install git && \
+    apt-get --assume-yes --quiet install libpng-dev && \
+    apt-get --assume-yes --quiet install rsync && \
+    apt-get --assume-yes --quiet install zip
+
+RUN curl --silent --show-error "https://getcomposer.org/installer" | php && \
+    mv "composer.phar" "/usr/local/bin/composer" && \
+    composer global require --no-interaction "phpunit/phpunit"
+
+RUN docker-php-ext-configure gd && \
+    docker-php-ext-install gd
+
+ENV PATH /root/.composer/vendor/bin:$PATH
+CMD ["bash"]
diff --git a/tests/dockerfiles/php81/attach.sh b/tests/dockerfiles/php81/attach.sh
new file mode 100755
index 0000000..8211a85
--- /dev/null
+++ b/tests/dockerfiles/php81/attach.sh
@@ -0,0 +1,3 @@
+# Attach to running container.
+
+docker exec --interactive --tty "php81" bash -l
diff --git a/tests/dockerfiles/php81/run.sh b/tests/dockerfiles/php81/run.sh
new file mode 100755
index 0000000..ced63cf
--- /dev/null
+++ b/tests/dockerfiles/php81/run.sh
@@ -0,0 +1,23 @@
+bash "1_build.sh"
+if [[ $? -ne 0 ]]; then
+    echo "Error: Build failed"
+    exit 1
+fi
+
+bash "2_start.sh"
+if [[ $? -ne 0 ]]; then
+    echo "Error: Start failed"
+    exit 1
+fi
+
+bash "3_test.sh"
+if [[ $? -ne 0 ]]; then
+    echo "Error: Test failed"
+    exit 1
+fi
+
+bash "4_stop.sh"
+if [[ $? -ne 0 ]]; then
+    echo "Error: Stop failed"
+    exit 1
+fi
diff --git a/tests/dockerfiles/php81/run_interactive.sh b/tests/dockerfiles/php81/run_interactive.sh
new file mode 100755
index 0000000..dee76fb
--- /dev/null
+++ b/tests/dockerfiles/php81/run_interactive.sh
@@ -0,0 +1,14 @@
+# Run image to create container and attach to it.
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+set -x
+cd "${SCRIPT_DIR}/../../.."
+project_dir="${PWD}"
+
+docker run \
+    --interactive \
+    --mount "type=bind,src=${project_dir},dst=/data,readonly=true" \
+    --name="php81" \
+    --rm \
+    --tty \
+    "php-curl-class/php81" /bin/bash