Multi-stage builds?

[jackfirth]

Docker now supports multi-stage builds to avoid putting build-only intermediate files and executables in the final output image. Might be worth investigating how that can help here?

[ccfontes]

Speaking of which, I'm trying to do multi-stage:

FROM racket/racket:8.8-full AS racket

FROM ghcr.io/stefan-hoeck/idris2-pack:nightly-230330 AS idris2-racket
ONBUILD COPY --from=racket /usr/bin/raco /usr/bin/raco
ONBUILD COPY --from=racket /usr/bin/racket /usr/bin/racket
ONBUILD COPY --from=racket /usr/share/racket /usr/share/racket
ONBUILD COPY --from=racket /usr/lib/racket /usr/lib/racket

but I get this error with raco:

RUN pack --cg racket build function.ipkg
/usr/bin/raco: Unrecognized command: exe

apt works just fine, so I'm wondering which files I missed COPYing.