The recent update of opam package ppx_deriving_yojson (3.10.1, Mar. 21) causes dependency issues resulting in a failed build of vyos1x-config/vyconf. The problem occurs in a newly built docker image after the vyos1x-config build pulls in v3.10.1, and the vyconf build attempts to downgrade back to v3.9.1.

This problem will manifest on the next update of the docker image. (One can manually trigger by 'opam upgrade' in the current container, which will update the list of available packages of 'default'.)

Consequently, we will constrain the package to the previous version in vyos1x-config.opam. The restriction will be dropped when dependencies are rationalized in community packages. The change will need to be propagated through hash updates for libvyosconfig, resp., vyos-1x before the next rebuild of the docker image.