Dockerfile

FROM mhart/alpine-node:10 as base
WORKDIR /usr/src
COPY . .
# copy all the source stuff, excepting everything in .dockerignore
RUN yarn
# creates node_modules/ populates with dependancies
RUN yarn build
#creates live/ populates with transpiled code
RUN yarn --production
#(I assume) recreates node_modules/ without or deletes build dependancies

FROM mhart/alpine-node:base-10
WORKDIR /usr/src
ENV NODE_ENV="production"
COPY --from=base /usr/src/live . 
#copies live/

#need to copy node_modules/ too but shouldn't I avoid multiple layers?
CMD ["node", "live"]