Container image size weirdness

[NiklasRosenstein]

The Nyl argocd-cmp image is surprisingly large with 730Mb. I did a bit of local testing: Installing git with apt-get adds something around 210Mb 😕 Using alpine instead with apk add git ends up at 90Mb.

But then also copying files from the other stages seems to make the image much larger than I would expect:

# BASE (with apk add git):
argocd-cmp   latest    c9b651397485   2 seconds ago   93.7MB

# COPY --from=argocd-bin /usr/local/bin/argocd /usr/local/bin/argocd
argocd-cmp   latest    e228c7a17ca2   41 seconds ago   235MB
68.2M   /usr/local/bin/argocd

# COPY --from=helm-bin /usr/local/bin/helm /usr/local/bin/helm
argocd-cmp   latest    0db34e373352   19 seconds ago   126MB
15.5M   /usr/local/bin/helm

# COPY --from=sops-bin /usr/local/bin/sops /usr/local/bin/sops
argocd-cmp   latest    dafe20ba4c05   8 seconds ago   112MB
9.0M    /usr/local/bin/sops

# COPY --from=build /opt/nyl /opt/nyl
argocd-cmp   latest    7db31b14a5f9   5 seconds ago   182MB
72.1M   /opt/nyl

The deltas here don't match up:

E.g. the argocd binary is 68Mb, but the image size grows by 141Mb when the file is copied from the stage.