FROM debian:stable-slim

# h3spec is a dynamically-linked Haskell binary; it needs libz and libgmp
# at runtime in addition to the usual ca-certificates for the download.
RUN apt-get update \
    && apt-get install -y --no-install-recommends \
        ca-certificates \
        curl \
        libgmp10 \
        zlib1g \
    && rm -rf /var/lib/apt/lists/*

ARG H3SPEC_VERSION=0.1.12
RUN curl -fsSL \
        "https://github.com/kazu-yamamoto/h3spec/releases/download/v${H3SPEC_VERSION}/h3spec-linux-x86_64" \
        -o /usr/local/bin/h3spec \
    && chmod +x /usr/local/bin/h3spec

ENTRYPOINT ["h3spec"]