[build] Dockerfile for builds.

etc/docker/Dockerfile

+FROM debian:10-slim as opam
+
+# ------------
+#   Get OPAM
+# ------------
+RUN apt-get update && apt-get install --no-install-recommends -y \
+    wget ca-certificates \
+    m4 bubblewrap gcc libc6-dev binutils make patch unzip
+
+# We need to install OPAM 2.0 manually for now.
+RUN wget https://github.com/ocaml/opam/releases/download/2.0.6/opam-2.0.6-x86_64-linux -O /usr/bin/opam && chmod 755 /usr/bin/opam
+
+# Basic OPAM setup
+ARG NJOBS=2
+ENV OPAMJOBS=${NJOBS}          \
+    OPAMROOT=/root/.opamcache  \
+    OPAMROOTISOK=true
+
+RUN opam init -a --bare --disable-sandboxing
+
+# -----------------
+# jsCoq pre-install
+# -----------------
+RUN opam switch create jscoq+64bit ocaml-base-compiler.4.07.1
+
+RUN apt install --no-install-recommends -y git rsync bzip2 nodejs curl
+RUN curl https://www.npmjs.com/install.sh | sh
+# ^ https://github.com/nodejs/help/issues/1877
+
+# ---------------------
+# jsCoq toolchain setup
+# ---------------------
+FROM opam as jscoq-prereq
+
+ARG REPO=https://github.com/jscoq/jscoq
+
+WORKDIR /root
+RUN git clone --recursive ${REPO}
+
+WORKDIR jscoq
+RUN ./etc/toolchain-setup.sh --64
+RUN opam clean -a -c
+
+# -----------
+# jsCoq build
+# -----------
+FROM jscoq-prereq as jscoq
+
+ARG NJOBS=4
+
+RUN git pull
+RUN eval $(opam env) && make coq && make jscoq
+
+# - addons
+RUN eval $(opam env) && make addons ADDONS="mathcomp"
+
+RUN eval $(opam env) && opam install -y elpi.1.8.0 && make addons ADDONS="elpi"
+
+RUN eval $(opam env) && make addons ADDONS="equations"
+
+# - remake packages after addon build
+#   (also creates `*.cma.js`)
+RUN eval $(opam env) && rm -rf _build/jscoq+64bit/coq-pkgs \
+       && make jscoq ADDONS="mathcomp elpi equations"
+
+# - dist tarballs
+RUN eval $(opam env) && make dist-tarball && make dist-npm \
+        && mkdir dist && mv _build/dist/*.tar.gz dist
+
+
+# jsCoq SDK
+
+#RUN cp -rL _build/install/jscoq+64bit/ ./dist && \
+#    rm dist/bin/*.byte dist/bin/*.opt \
+#       dist/lib/coq/*/*.cmxs \
+#       `find dist -regex '.*\.\(cm\(a\|t\|ti\)\|mli?\)'`
+
+#FROM debian:10-slim
+
+#COPY --from=0 /root/jscoq/dist /opt/jscoq
+

etc/docker/Makefile

+.PHONY: build dist serve
+
+WHO = jscoq
+
+export REPO = https://github.com/$(WHO)/jscoq
+export NJOBS ?= 4
+
+ARGS = --build-arg REPO --build-arg NJOBS
+
+build:
+	docker build . --target opam         $(ARGS)  -t opam
+	docker build . --target jscoq-prereq $(ARGS)  -t jscoq:prereq
+	docker build . --target jscoq        $(ARGS)  -t jscoq
+
+dist:
+	docker run --name jscoq-get-dist jscoq
+	docker cp jscoq-get-dist:/root/jscoq/dist .
+	docker rm jscoq-get-dist
+
+serve:
+	docker run --publish 8080:8080 --rm -it jscoq \
+		bash -c "npx http-server _build/dist"