Dockerfile

# Find eligible builder and runner images on Docker Hub. We use Ubuntu/Debian instead of
# Alpine to avoid DNS resolution issues in production.
#
# https://hub.docker.com/r/hexpm/elixir/tags?page=1&name=ubuntu
# https://hub.docker.com/_/ubuntu?tab=tags
#
#
# This file is based on these images:
#
#   - https://hub.docker.com/r/hexpm/elixir/tags - for the build image
#   - https://hub.docker.com/_/debian?tab=tags&page=1&name=bullseye-20210902-slim - for the release image
#   - https://pkgs.org/ - resource for finding needed packages
#   - Ex: hexpm/elixir:1.14.0-erlang-25.0.3-debian-bullseye-20210902-slim
#
ARG ELIXIR_VERSION=1.18.2
ARG OTP_VERSION=27.2.1
ARG DEBIAN_VERSION=bullseye-20250203-slim

ARG BUILDER_IMAGE="hexpm/elixir:${ELIXIR_VERSION}-erlang-${OTP_VERSION}-debian-${DEBIAN_VERSION}"
ARG RUNNER_IMAGE="debian:${DEBIAN_VERSION}"

FROM ${BUILDER_IMAGE} as builder

# Install build dependencies
RUN apt-get update -y && apt-get install -y build-essential git curl cmake libclang-dev\
  && apt-get clean && rm -f /var/lib/apt/lists/*_*

# Install Rust
RUN curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y
ENV PATH="/root/.cargo/bin:${PATH}"

# Prepare build dir
WORKDIR /app

# Install hex + rebar
RUN mix local.hex --force && \
  mix local.rebar --force

# Set build ENV
ENV MIX_ENV="prod"

# Install mix dependencies
COPY mix.exs mix.lock VERSION ./
RUN mix deps.get --only $MIX_ENV
RUN mkdir config

# Copy compile-time config files
COPY config/config.exs config/${MIX_ENV}.exs config/
RUN mix deps.compile

COPY priv priv
COPY lib lib
COPY native native

# Compile the release
RUN mix compile

# Changes to config/runtime.exs don't require recompiling the code
COPY config/runtime.exs config/

COPY rel rel
RUN mix release supavisor

# Start a new build stage for the final image
FROM ${RUNNER_IMAGE}

RUN apt-get update -y && apt-get install -y libstdc++6 openssl libncurses5 locales vim curl htop postgresql-contrib sudo tini cmake libclang-dev \
  && apt-get clean && rm -f /var/lib/apt/lists/*_*

# Set the locale
RUN sed -i '/en_US.UTF-8/s/^# //g' /etc/locale.gen && locale-gen

ENV LANG en_US.UTF-8
ENV LANGUAGE en_US:en
ENV LC_ALL en_US.UTF-8

WORKDIR "/app"
RUN chown nobody /app

# Set runner ENV
ENV MIX_ENV="prod"

# Only copy the final release from the build stage
COPY --from=builder --chown=nobody:root /app/_build/${MIX_ENV}/rel/supavisor ./

ENV RLIMIT_NOFILE 100000
COPY limits.sh /app/limits.sh
ENTRYPOINT ["/usr/bin/tini", "-s", "-g", "--", "/app/limits.sh"]

CMD ["/app/bin/server"]
# Appended by flyctl
ENV ECTO_IPV6 true
ENV ERL_AFLAGS "-proto_dist inet6_tcp"