A multi-stage build could be used to install this, no?

FROM just as just

FROM python

COPY --from=just /bin/just /bin/just

# Copy everything in the current directory - use .containerignore / .dockerignore
COPY . .

just

Has the added benefit of being able to try out just.

It probably shouldn't be recommended as the base, but perhaps having some common distros like alpine, debian, and ubuntu would be nice for those trying it out or not wanting to pull down layers.

A con is the overhead of having other stuff in the image but it seems like it would be better than downloading it in a podman/docker command. Or maybe some are distributing container images that can only be used for copying like above.

My current suggestion is just to have a bare distroless container containing just so you can use the above commands to add the just static binary to any container.