# The remote executor's image.
#
# buck2 fetches its own toolchains — zig, rustc, the Rust standard library, the
# NDK — from the pins in scripts/*.dotslash, so almost nothing here has to be
# installed. Almost: a handful of `-sys` crates ask pkg-config where a system
# library is, and one of them then links against it.
#
# That is why this image exists rather than gcr.io/flame-public/rbe-ubuntu24-04,
# which carries neither. Without pkg-config, alsa-sys's build script panics
# before it can emit a single link directive; without libasound2-dev, the flags
# it emits name a library the linker cannot find.
#
# 24.04 for the same reason the public image was pinned to it: a build script is
# compiled here and *run* on the worker, and 22.04's glibc 2.35 is old enough to
# fail that before a crate is compiled.
FROM ubuntu:24.04

# ca-certificates because an action fetches over TLS, and python3 because the
# prelude's own Rust rules shell out to it — a dep-file pass runs on the worker,
# not here. The rest is the system half of what the graph's build scripts look
# for: alsa-sys asks pkg-config for libasound, and v4l2r runs bindgen over
# `linux/videodev2.h`, which needs libclang to parse it and the kernel's own
# headers to find it — and libc's own, since videodev2.h includes <sys/time.h>. A cargo build takes both from the justfile's environment,
# which names this machine's zig headers — nothing a remote action inherits, so
# the worker has to carry them.
#
# libclang1 and its builtin headers rather than libclang-dev, which drags the
# whole clang toolchain in and took the image from 130 MB to 731 MB. bindgen
# loads the library and reads those headers; it has no use for the compiler.
#
# Kept to what a build has actually asked for: an unused package here is an
# image every action pulls.
RUN apt-get update && apt-get install --no-install-recommends -y \
        ca-certificates \
        libasound2-dev \
        libc6-dev \
        libclang1-18 \
        libclang-common-18-dev \
        linux-libc-dev \
        pkg-config \
        python3 \
    && rm -rf /var/lib/apt/lists/*