One app docker image for build frontend & backend

Dockerfile

FROM node:14-alpine as node
FROM ruby:2.7.0-alpine3.11 as build-base

COPY --from=node /usr/local/bin/node /usr/local/bin/
COPY --from=node /opt/yarn-v1.22.4 /opt/yarn-v1.22.4

RUN ln -s /usr/local/bin/node /usr/local/bin/nodejs

# Here is you can copy npm from node to build-base if you preffer use it
RUN ln -s /opt/yarn-v1.22.4/bin/yarn /usr/local/bin/yarn
RUN ln -s /opt/yarn-v1.22.4/bin/yarnpkg /usr/local/bin/yarnpkg

RUN node --version

RUN mkdir -p /app
WORKDIR /app

COPY . ./

# install app server deps
RUN gem update --system
RUN gem install bundler:2.1.4
RUN bundle config --global jobs $(nproc --all)
RUN bundle install

# install frontend deps
RUN yarn install

# optinal copy entrypoint inside image
# COPY docker/entrypoint.sh /usr/bin/
# RUN chmod +x /usr/bin/entrypoint.sh
# ENTRYPOINT ["entrypoint.sh"]