Yes thanks @kit-ty-kate. As written in DEVEL.md in general my projects do depend on the development version of b0.
At the moment it’s a bit painful because I’m trying to dogfood and improve the upcoming cmdliner completion support so you also need a pin on cmdliner which may break a few important package you have in your switch like odoc or ocp-indent (but pinning their dev version aswell should do it).