diff --git a/Dockerfile b/Dockerfile
index 4a0a69e..7c1eeaf 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -210,6 +210,21 @@ RUN export OS_VERSION=$(cat /etc/os-release | grep VERSION_ID | cut -d '"' -f2)
         php8.2-xml \
         php8.2-xsl \
         php8.2-zip \
+        \
+        php8.3-cli \
+        php8.3-bz2 \
+        php8.3-curl \
+        php8.3-dev \
+        php8.3-fileinfo \
+        php8.3-intl \
+        php8.3-mbstring \
+        php8.3-phar \
+        php8.3-phpdbg \
+        php8.3-readline \
+        php8.3-sockets \
+        php8.3-xml \
+        php8.3-xsl \
+        php8.3-zip \
     && apt autoremove -y \
     && apt clean
 
@@ -250,7 +265,7 @@ COPY composer.json \
 
 RUN cd /tools \
     # Install `ext-bcmath` as it seems to be a requirement for `roave/backward-compatibility-check`
-    && apt install -y php-bcmath \
+    && apt install -y php-bcmath php8.3-bcmath \
     && composer install \
         --classmap-authoritative
 
diff --git a/README.md b/README.md
index 53ea9fa..86dc3ce 100644
--- a/README.md
+++ b/README.md
@@ -237,6 +237,7 @@ The container the action provides and consumes builds off the ubuntu:focal image
 - 8.0
 - 8.1
 - 8.2
+- 8.3
 
 Each provides the following extensions by default:
 
diff --git a/scripts/php_ini_dev_settings.sh b/scripts/php_ini_dev_settings.sh
index 5f92d0d..f3e68b1 100755
--- a/scripts/php_ini_dev_settings.sh
+++ b/scripts/php_ini_dev_settings.sh
@@ -14,7 +14,7 @@ SUBSTITUTIONS+=('s/mysqlnd.collect_memory_statistics ?= ?(On|Off)/mysqlnd.collec
 SUBSTITUTIONS+=('s/zend.assertions ?= ?(-1|1)/zend.assertions = 1/')
 SUBSTITUTIONS+=('s/opcache.huge_code_pages ?= ?(0|1)/opcache.huge_code_pages = 0/')
 
-for PHP_VERSION in 5.6 7.0 7.1 7.2 7.3 7.4 8.0 8.1 8.2;do
+for PHP_VERSION in 5.6 7.0 7.1 7.2 7.3 7.4 8.0 8.1 8.2 8.3;do
     for PHP_SAPI in cli phpdbg; do
         INI_FILE="/etc/php/${PHP_VERSION}/${PHP_SAPI}/php.ini"
         for SUBSTITUTION in "${SUBSTITUTIONS[@]}";do