diff --git a/Makefile b/Makefile
index 6606b23..254b415 100644
--- a/Makefile
+++ b/Makefile
@@ -1,6 +1,6 @@
 .PHONY: all clean docker-build docker-images help lint lint-fix repl shell test test-static test-unit bump bump-dev process-reports
 
-IMAGE ?= php_8_3
+IMAGE ?= php_8_4
 PHP = docker compose run --rm php
 
 all: test
diff --git a/composer.json b/composer.json
index 8d6899c..f3efbbd 100644
--- a/composer.json
+++ b/composer.json
@@ -23,7 +23,7 @@
         "php": ">=5.3.0"
     },
     "require-dev": {
-        "phpstan/phpstan": "1.12.0",
+        "phpstan/phpstan": "1.12.11",
         "phpunit/phpunit": "^9.5.20",
         "squizlabs/php_codesniffer": "3.*",
         "symfony/yaml": "^5.4.40",
diff --git a/docker-compose.yml b/docker-compose.yml
index d6354f4..553272d 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -1,6 +1,6 @@
 services:
   php:
-    build: ./docker/image/${IMAGE:-php_8_3}
+    build: ./docker/image/${IMAGE:-php_8_4}
     volumes:
       - .:/app
       - ${COMPOSER_HOME:-$HOME/.composer}:/tmp
diff --git a/docker/image/php_8_4/Dockerfile b/docker/image/php_8_4/Dockerfile
index 7c5b4ce..cf0d186 100644
--- a/docker/image/php_8_4/Dockerfile
+++ b/docker/image/php_8_4/Dockerfile
@@ -1,4 +1,4 @@
-FROM php:8.4-rc-cli
+FROM php:8.4-cli
 
 RUN apt-get update && apt-get install -y \
     bash \
@@ -7,6 +7,10 @@ RUN apt-get update && apt-get install -y \
     zip \
     wget
 
-COPY --from=composer:2.7 /usr/bin/composer /usr/bin/composer
+RUN pecl install xdebug-3.4.0beta1
+
+RUN docker-php-ext-enable xdebug
+
+COPY --from=composer:2.8 /usr/bin/composer /usr/bin/composer
 
 WORKDIR /app