diff --git a/5.3/Dockerfile b/5.3/Dockerfile
index 5a8aa0e..a00eeff 100644
--- a/5.3/Dockerfile
+++ b/5.3/Dockerfile
@@ -4,6 +4,9 @@ FROM wodby/base-php:${FROM_TAG}
 
 ARG PHP_DEV
 
+ARG WODBY_USER_ID=1000
+ARG WODBY_GROUP_ID=1000
+
 ENV PHP_DEV="${PHP_DEV}" \
     SSHD_PERMIT_USER_ENV="yes" \
     RABBITMQ_C_VER="0.8.0" \
@@ -31,8 +34,14 @@ ENV PHP_DEV="${PHP_DEV}" \
 
 RUN set -xe; \
     \
-	addgroup -g 1000 -S wodby; \
-	adduser -u 1000 -D -S -s /bin/bash -G wodby wodby; \
+    # Delete existing user/group if uid/gid occupied.
+    existing_group=$(getent group "${WODBY_GROUP_ID}" | cut -d: -f1); \
+    if [[ -n "${existing_group}" ]]; then delgroup "${existing_group}"; fi; \
+    existing_user=$(getent passwd "${WODBY_USER_ID}" | cut -d: -f1); \
+    if [[ -n "${existing_user}" ]]; then deluser "${existing_user}"; fi; \
+    \
+	addgroup -g "${WODBY_GROUP_ID}" -S wodby; \
+	adduser -u "${WODBY_USER_ID}" -D -S -s /bin/bash -G wodby wodby; \
 	adduser wodby www-data; \
 	sed -i '/^wodby/s/!/*/' /etc/shadow; \
 	echo "PS1='\w\$ '" >> /home/wodby/.bashrc; \
diff --git a/5.3/Makefile b/5.3/Makefile
index a9557a6..da87c41 100644
--- a/5.3/Makefile
+++ b/5.3/Makefile
@@ -7,6 +7,9 @@ REPO = wodby/php
 NAME = php-$(PHP_VER_MINOR)
 FROM_TAG = $(PHP_VER)
 
+WODBY_USER_ID ?= 1000
+WODBY_GROUP_ID ?= 1000
+
 ifeq ($(TAG),)
     ifneq ($(PHP_DEBUG),)
         TAG ?= $(PHP_VER_MINOR)-debug
@@ -42,6 +45,8 @@ build:
 		--build-arg FROM_TAG=$(FROM_TAG) \
 		--build-arg PHP_DEV=$(PHP_DEV) \
 		--build-arg PHP_DEBUG=$(PHP_DEBUG) \
+		--build-arg WODBY_USER_ID=$(WODBY_USER_ID) \
+		--build-arg WODBY_GROUP_ID=$(WODBY_GROUP_ID) \
 		./
 
 test:
diff --git a/5.6/Dockerfile b/5.6/Dockerfile
index bd2da5a..cfab054 100644
--- a/5.6/Dockerfile
+++ b/5.6/Dockerfile
@@ -5,6 +5,9 @@ FROM wodby/base-php:${FROM_TAG}
 ARG PHP_DEV
 ARG PHP_DEBUG
 
+ARG WODBY_USER_ID=1000
+ARG WODBY_GROUP_ID=1000
+
 ENV PHP_DEV="${PHP_DEV}" \
     PHP_DEBUG="${PHP_DEBUG}" \
     SSHD_PERMIT_USER_ENV="yes" \
@@ -53,8 +56,14 @@ ENV APP_ROOT="/var/www/html" \
 
 RUN set -xe; \
     \
-	addgroup -g 1000 -S wodby; \
-	adduser -u 1000 -D -S -s /bin/bash -G wodby wodby; \
+    # Delete existing user/group if uid/gid occupied.
+    existing_group=$(getent group "${WODBY_GROUP_ID}" | cut -d: -f1); \
+    if [[ -n "${existing_group}" ]]; then delgroup "${existing_group}"; fi; \
+    existing_user=$(getent passwd "${WODBY_USER_ID}" | cut -d: -f1); \
+    if [[ -n "${existing_user}" ]]; then deluser "${existing_user}"; fi; \
+    \
+	addgroup -g "${WODBY_GROUP_ID}" -S wodby; \
+	adduser -u "${WODBY_USER_ID}" -D -S -s /bin/bash -G wodby wodby; \
     adduser wodby www-data; \
 	sed -i '/^wodby/s/!/*/' /etc/shadow; \
 	echo "PS1='\w\$ '" >> /home/wodby/.bashrc; \
diff --git a/5.6/Makefile b/5.6/Makefile
index 36e2841..d5e5861 100644
--- a/5.6/Makefile
+++ b/5.6/Makefile
@@ -7,6 +7,9 @@ REPO = wodby/php
 NAME = php-$(PHP_VER_MINOR)
 FROM_TAG = $(PHP_VER)
 
+WODBY_USER_ID ?= 1000
+WODBY_GROUP_ID ?= 1000
+
 ifeq ($(TAG),)
     ifneq ($(PHP_DEBUG),)
         TAG ?= $(PHP_VER_MINOR)-debug
@@ -42,6 +45,8 @@ build:
 		--build-arg FROM_TAG=$(FROM_TAG) \
 		--build-arg PHP_DEV=$(PHP_DEV) \
 		--build-arg PHP_DEBUG=$(PHP_DEBUG) \
+		--build-arg WODBY_USER_ID=$(WODBY_USER_ID) \
+		--build-arg WODBY_GROUP_ID=$(WODBY_GROUP_ID) \
 		./
 
 test:
diff --git a/7/Dockerfile b/7/Dockerfile
index 8d51ad0..0e47f42 100644
--- a/7/Dockerfile
+++ b/7/Dockerfile
@@ -5,6 +5,9 @@ FROM wodby/base-php:${FROM_TAG}
 ARG PHP_DEV
 ARG PHP_DEBUG
 
+ARG WODBY_USER_ID=1000
+ARG WODBY_GROUP_ID=1000
+
 ENV PHP_DEV="${PHP_DEV}" \
     PHP_DEBUG="${PHP_DEBUG}" \
     SSHD_PERMIT_USER_ENV="yes" \
@@ -56,8 +59,14 @@ ENV APP_ROOT="/var/www/html" \
 
 RUN set -xe; \
     \
-	addgroup -g 1000 -S wodby; \
-	adduser -u 1000 -D -S -s /bin/bash -G wodby wodby; \
+    # Delete existing user/group if uid/gid occupied.
+    existing_group=$(getent group "${WODBY_GROUP_ID}" | cut -d: -f1); \
+    if [[ -n "${existing_group}" ]]; then delgroup "${existing_group}"; fi; \
+    existing_user=$(getent passwd "${WODBY_USER_ID}" | cut -d: -f1); \
+    if [[ -n "${existing_user}" ]]; then deluser "${existing_user}"; fi; \
+    \
+	addgroup -g "${WODBY_GROUP_ID}" -S wodby; \
+	adduser -u "${WODBY_USER_ID}" -D -S -s /bin/bash -G wodby wodby; \
 	adduser wodby www-data; \
 	sed -i '/^wodby/s/!/*/' /etc/shadow; \
 	echo "PS1='\w\$ '" >> /home/wodby/.bashrc; \
diff --git a/7/Makefile b/7/Makefile
index 17e1bbf..0da60da 100644
--- a/7/Makefile
+++ b/7/Makefile
@@ -7,6 +7,9 @@ REPO = wodby/php
 NAME = php-$(PHP_VER_MINOR)
 FROM_TAG = $(PHP_VER)
 
+WODBY_USER_ID ?= 1000
+WODBY_GROUP_ID ?= 1000
+
 ifeq ($(TAG),)
     ifneq ($(PHP_DEBUG),)
         TAG ?= $(PHP_VER_MINOR)-debug
@@ -42,6 +45,8 @@ build:
 		--build-arg FROM_TAG=$(FROM_TAG) \
 		--build-arg PHP_DEV=$(PHP_DEV) \
 		--build-arg PHP_DEBUG=$(PHP_DEBUG) \
+		--build-arg WODBY_USER_ID=$(WODBY_USER_ID) \
+		--build-arg WODBY_GROUP_ID=$(WODBY_GROUP_ID) \
 		./
 
 test: