diff --git a/7.4-ci/Dockerfile b/7.4-ci/Dockerfile
index a41f1e9..b72735d 100644
--- a/7.4-ci/Dockerfile
+++ b/7.4-ci/Dockerfile
@@ -19,7 +19,7 @@ RUN apk add --no-cache \
     curl -sS https://getcomposer.org/installer | php -- --install-dir=/usr/local/bin --filename=composer
 
 # PHP Extensions
-ENV PHPIZE_DEPS \
+ENV PHPIZE_DEPS="\
     autoconf \
     cmake \
     file \
@@ -33,7 +33,7 @@ ENV PHPIZE_DEPS \
     pcre-dev \
     pkgconf \
     re2c \
-    zlib-dev
+    zlib-dev"
 
 RUN apk add --no-cache --virtual .build-deps \
     $PHPIZE_DEPS && \
diff --git a/8.0-ci/Dockerfile b/8.0-ci/Dockerfile
index 0ec4119..29ca957 100644
--- a/8.0-ci/Dockerfile
+++ b/8.0-ci/Dockerfile
@@ -19,7 +19,7 @@ RUN apk add --no-cache \
     curl -sS https://getcomposer.org/installer | php -- --install-dir=/usr/local/bin --filename=composer
 
 # PHP Extensions
-ENV PHPIZE_DEPS \
+ENV PHPIZE_DEPS="\
     autoconf \
     cmake \
     file \
@@ -33,7 +33,7 @@ ENV PHPIZE_DEPS \
     pcre-dev \
     pkgconf \
     re2c \
-    zlib-dev
+    zlib-dev"
 
 RUN apk add --no-cache --virtual .build-deps \
     $PHPIZE_DEPS && \
diff --git a/8.1-ci/Dockerfile b/8.1-ci/Dockerfile
index 0844d86..3ab6daa 100644
--- a/8.1-ci/Dockerfile
+++ b/8.1-ci/Dockerfile
@@ -19,7 +19,7 @@ RUN apk add --no-cache \
     curl -sS https://getcomposer.org/installer | php -- --install-dir=/usr/local/bin --filename=composer
 
 # PHP Extensions
-ENV PHPIZE_DEPS \
+ENV PHPIZE_DEPS="\
     autoconf \
     cmake \
     file \
@@ -33,7 +33,7 @@ ENV PHPIZE_DEPS \
     pcre-dev \
     pkgconf \
     re2c \
-    zlib-dev
+    zlib-dev"
 
 RUN apk add --no-cache --virtual .build-deps \
     $PHPIZE_DEPS && \
diff --git a/8.2-ci/Dockerfile b/8.2-ci/Dockerfile
index 1b6ca3a..b5f9a9e 100644
--- a/8.2-ci/Dockerfile
+++ b/8.2-ci/Dockerfile
@@ -19,7 +19,7 @@ RUN apk add --no-cache \
     curl -sS https://getcomposer.org/installer | php -- --install-dir=/usr/local/bin --filename=composer
 
 # PHP Extensions
-ENV PHPIZE_DEPS \
+ENV PHPIZE_DEPS="\
     autoconf \
     cmake \
     file \
@@ -33,7 +33,7 @@ ENV PHPIZE_DEPS \
     pcre-dev \
     pkgconf \
     re2c \
-    zlib-dev
+    zlib-dev"
 
 RUN apk add --no-cache --virtual .build-deps \
     $PHPIZE_DEPS && \
diff --git a/8.3-ci/Dockerfile b/8.3-ci/Dockerfile
index 3a0ea05..8813d88 100644
--- a/8.3-ci/Dockerfile
+++ b/8.3-ci/Dockerfile
@@ -19,7 +19,7 @@ RUN apk add --no-cache \
     curl -sS https://getcomposer.org/installer | php -- --install-dir=/usr/local/bin --filename=composer
 
 # PHP Extensions
-ENV PHPIZE_DEPS \
+ENV PHPIZE_DEPS="\
     autoconf \
     cmake \
     file \
@@ -33,7 +33,7 @@ ENV PHPIZE_DEPS \
     pcre-dev \
     pkgconf \
     re2c \
-    zlib-dev
+    zlib-dev"
 
 RUN apk add --no-cache --virtual .build-deps \
     $PHPIZE_DEPS && \