CMD ["./myprogram"]

If you actually meant docker + tar (e.g., docker save ), let me know and I can provide a similar guide for that.

docker run --rm -v $(pwd):/data gcc:latest ar t /data/libmylib.a ar t lists the object files inside the archive. If you need to pull an object file from an existing static library:

docker run --rm -v $(pwd):/data gcc:latest ar x /data/libmylib.a mylib.o FROM alpine:latest AS builder RUN apk add --no-cache gcc musl-dev make