Using Docker to Host Zencart (PHP 7.3.33) - php

Question

I have set up Docker Compose to build a PHP environment hosted by Nginx in order to run a Zencart site. I have viewed a few different walkthroughs and forums, and have gotten very close to having a functional implementation.
For some reason, Zencart fails to recognize the presence of the Zip and GD (GD Imaging) modules, despite them being enabled in the parser. I suspect there may be some sort of incompatibility in the version of the modules used versus the version of PHP installed.
Zencart claims to only support PHP versions before 7.4. I do not know if the modules installed are also dependent on the version of PHP used, or if they may be intended for a later version.
I have attached images of the PHP configuration, along with the requirements screen for the Zencart instance I am running. Zencart's requirements are nearly met, save for GD and Zip, as indicated. Also attached are the Docker Compose YAML file, the PHP docker file, and the NGINX docker file.
Any help that can be given in deciphering this mystery would be greatly appreciated.
docker-compose.yml
version: '3'
services:
php:
image: harbor.my-host.hosting/express/php:${RELEASE_TAG:-edge}
build:
context: .
dockerfile: dockerfiles/php.dockerfile
args:
- UID=${UID:-1000}
- GID=${GID:-1000}
# environment:
# - WIDGET_DB_HOST=${WIDGET_DB_HOST}
# - WIDGET_DB_UNAME=${WIDGET_DB_UNAME}
# - WIDGET_DB_PWD=${WIDGET_DB_PWD}
# - WIDGET_DB_NAME=${WIDGET_DB_NAME}
# - QUEUE_DB_HOST=${QUEUE_DB_HOST}
# - QUEUE_DB_UNAME=${QUEUE_DB_UNAME}
# - QUEUE_DB_PWD=${QUEUE_DB_PWD}
# - QUEUE_DB_NAME=${QUEUE_DB_NAME}
volumes:
- ./src:/var/www/html:consistent
networks:
- php-app
nginx:
image: harbor.my-host.hosting/express/nginx:${RELEASE_TAG:-edge}
build:
context: .
dockerfile: dockerfiles/nginx.dockerfile
args:
- UID=${UID:-1000}
- GID=${GID:-1000}
volumes:
- ./src:/var/www/html:consistent
ports:
- 8080:80
depends_on:
- php
networks:
- php-app
networks:
php-app:
external: false
php.dockerfile
FROM php:7.3-fpm-alpine
ARG UID
ARG GID
ENV UID=${UID}
ENV GID=${GID}
RUN apk add --no-cache --virtual \
build-essentials \
mysql-client \
icu-dev \
icu-libs \
zlib-dev \
g++ \
make \
automake \
autoconf \
libzip-dev \
freetype \
libjpeg-turbo-dev \
libpng-dev \
zip \
unzip
RUN docker-php-ext-install mysqli && \
docker-php-ext-install pdo_mysql && \
docker-php-ext-install exif && \
docker-php-ext-install mbstring && \
docker-php-ext-install zip && \
docker-php-ext-install gd && \
docker-php-ext-configure gd && \
docker-php-ext-enable gd && \
docker-php-ext-enable exif && \
docker-php-ext-enable zip && \
apk del build-essentials && rm -rf /usr/src/php*
WORKDIR /var/www/html
# MacOS staff group's gid is 20, so is the dialout group in alpine linux. We're not using it, let's just remove it.
RUN delgroup dialout
RUN addgroup -g ${GID} --system phpapp
RUN adduser -G phpapp --system -D -s /bin/sh -u ${UID} phpapp
RUN sed -i "s/user = www-data/user = phpapp/g" /usr/local/etc/php-fpm.d/www.conf
RUN sed -i "s/group = www-data/group = phpapp/g" /usr/local/etc/php-fpm.d/www.conf
RUN echo "php_admin_flag[log_errors] = true" >> /usr/local/etc/php-fpm.d/www.conf
RUN echo "php_admin_flag[display_errors] = off" >> /usr/local/etc/php-fpm.d/www.conf
COPY src /var/www/html
RUN chown -R phpapp /var/www/html
CMD ["php", "artisan", "key:generate"]
CMD ["php", "artisan", "config:cache"]
CMD ["php-fpm", "-y", "/usr/local/etc/php-fpm.conf", "-R"]
nginx.dockerfile
FROM nginx:stable-alpine
ARG UID
ARG GID
ENV UID=${UID}
ENV GID=${GID}
# MacOS staff group's gid is 20, so is the dialout group in alpine linux. We're not using it, let's just remove it.
RUN delgroup dialout
RUN addgroup -g ${GID} --system phpapp
RUN adduser -G phpapp --system -D -s /bin/sh -u ${UID} phpapp
RUN sed -i "s/user nginx/user phpapp/g" /etc/nginx/nginx.conf
ADD ./dockerfiles/nginx/default.conf /etc/nginx/conf.d/
COPY src /var/www/html
RUN chown -R phpapp /var/www/html