Feature proposal: Build Docker images with 0install

I would like to propose a small addition to 0install that I believe would
work great with Docker multi-stage builds
(https://docs.docker.com/develop/develop-images/multistage-build/).

A new command-line options for the "0install run" command, called something
like --print-script:
Everything runs as usual (select, download, etc.) right up until the point
where the target application would be executed. Now instead an equivalent
shell script is printed to stdout.
Basically this would mean encoding and printing the output get_exec_args
(https://github.com/0install/0install/blob/master/ocaml/zeroinstall/exec.ml#
L109) like this:
#!/bin/sh
VAR1=/root/.cache/0install.net/implementations/sha256_ABC123
/root/.cache/0install.net/implementations/sha256_DEF456/myapp

With this feature it would now be possible to use 0install to download an
app and its dependencies in Docker but then use that app without having to
include 0install in the final image:

FROM some-image-with-0install as builder
RUN 0install run --print-shell http://example.com/feed.xml > /app
RUN chmod +x /app
FROM debian
COPY --from=builder /root/.cache/0install.net /root/.cache/0install.net
COPY --from=builder /app /app
ENTRYPOINT ["./app"]

Another usecase for this would be sandbox tools. For example:
The new Windows Sandbox feature in Windows 10 automatically creates
light-weight throw-away VMs for testing untrusted software. Zero Install
could resolve and download dependencies outside of the sandbox and then
mount the implementation cache directory and a (Windows) shell script into
the sandbox VM.