anchor.diff:  #   https://hub.docker.com/r/augustoroman/v8-lib/
   #
   # Once that is available, build this docker image using:
  -#   docker build --build-arg V8_VERSION=6.7.77 -t gov8 .
  +#   docker build --build-arg V8_VERSION=6.7.77 -t v8-runjs .
   # and then run the interactive js using:
  -#   docker run -it --rm gov8
  +#   docker run -it --rm v8-runjs
   FROM ${V8_SOURCE_IMAGE}:${V8_VERSION} as v8
   
  -FROM ubuntu:16.04
  -# Install the basics we need to compile and install stuff.
  -# In particular, we'll need curl for installing go and build-essential for
  -# gcc.
  -RUN apt-get update -qq \
  -    && apt-get install -y --no-install-recommends ca-certificates curl build-essential git \
  -    && rm -rf /var/lib/apt/lists/*
  -
  -# Download and install go.
  -RUN curl -JL https://dl.google.com/go/go1.10.2.linux-amd64.tar.gz \
  -    | tar -C /usr/local -xz
  -ENV PATH=$PATH:/usr/local/go/bin
  -
  -# ------------ Build and run v8 go tests ---------------------------------
  +# ------------ Build go v8 library and run tests ----------------------------
  +FROM golang as builder
   # Copy the v8 code from the local disk, similar to:
   #   RUN go get github.com/augustoroman/v8 ||:
   # but this allows using any local modifications.
  -ARG GO_V8_DIR=/root/go/src/github.com/augustoroman/v8/
  +ARG GO_V8_DIR=/go/src/github.com/augustoroman/v8/
   ADD *.go *.h *.cc $GO_V8_DIR
   ADD cmd $GO_V8_DIR/cmd/
   ADD v8console $GO_V8_DIR/v8console/
  
positive.code: ARG V8_VERSION
  ARG V8_SOURCE_IMAGE=augustoroman/v8-lib
  
  # The v8 library & include files are taken from a pre-built docker image that
  # is expected to be called v8-lib. You can build that locally using:
  #   docker build --build-arg V8_VERSION=6.7.77 --tag augustoroman/v8-lib:6.7.77 docker-v8-lib/
  
negative.code: RUN go get ./...
  RUN go test ./...
  
  # ------------ Build the final container for v8-runjs -----------------------
  # TODO(aroman) find a smaller container for the executable! For some reason,
  # scratch, alpine, and busybox don't work. I wonder if it has something to do
  # with cgo?
  FROM ubuntu:16.04
  COPY --from=builder /go/bin/v8-runjs /v8-runjs
  CMD /v8-runjs
  