Dockerfile

FROM bitwalker/alpine-elixir:1.10.2 as releaser

WORKDIR /app

# Install Hex + Rebar
RUN mix do local.hex --force, local.rebar --force

COPY config/ /app/config/
COPY mix.exs /app/
COPY mix.* /app/

ENV MIX_ENV=prod
RUN mix do deps.get --only $MIX_ENV, deps.compile

# build project
COPY . /app/
COPY node_modules /app/
COPY package-lock.json /app/
RUN mix compile

# build release
WORKDIR /app
RUN MIX_ENV=prod mix release

########################################################################

FROM bitwalker/alpine-elixir:1.10.2

EXPOSE 4004
ENV PORT=4004 \
    MIX_ENV=prod \
    SHELL=/bin/bash

WORKDIR /app
COPY --from=releaser app/_build/prod/rel/sock_app .
COPY --from=releaser app/bin/ ./bin

CMD ["./bin/start"]