diff --git a/docker/php/Dockerfile b/docker/php/Dockerfile
index 5efc229..2ab5f55 100644
--- a/docker/php/Dockerfile
+++ b/docker/php/Dockerfile
@@ -14,10 +14,11 @@ RUN apk add --no-cache \
     npm
 
 # Install PHP extensions
-RUN docker-php-ext-configure intl \
-    && docker-php-ext-install -j$(nproc) intl pdo pdo_mysql opcache zip \
+RUN docker-php-source extract \
+    && docker-php-ext-configure intl \
+    && docker-php-ext-install -j$(nproc) intl pdo pdo_mysql opcache zip tokenizer ctype iconv mbstring \
     && docker-php-ext-install dom xml simplexml xmlreader xmlwriter \
-    && docker-php-ext-install -j$(nproc) tokenizer ctype iconv mbstring
+    && docker-php-source delete
 
 # Install composer
 ENV COMPOSER_ALLOW_SUPERUSER=1 \