Generate static deltas

[oleid]

I'm using flat-manager to host self-made applications. This works fine, but I noticed downloads can be slow if the application is big.

Digging the docs, it turned out that static deltas are the way to go! And indeed, running

$ flatpak build-update-repo  --gpg-sign=$KEY  --generate-static-deltas /srv/flatpak/myrepo

solves the issue.

While flat-manager actually runs flatpak build-update-repo, no static deltas are generated (=--generate-static-deltas is not set).

What is the recommended way to generate provide deltas? (i.e. for first-time app installations or updating via the flatpak command).

If it is --generate-static-deltas, would you accept a patch to enable the feature per repo on-demand?