FROM alpine RUN apk update && \ apk upgrade RUN apk add ruby build-base ruby-dev sqlite-dev RUN gem install --no-document sinatra data_mapper dm-sqlite-adapter bigdecimal puma etc COPY webapp.rb config.ru /hlbb/ COPY views/* /hlbb/views/ WORKDIR /hlbb ENTRYPOINT ["puma", "-e", "production", "-p", "8080"]