FYI, running just by itself isn’t printing the available commands as the discussion above indicates it should. Instead, I get the message error: Justfile contains no default recipe.
My ~/.justfile just imports /usr/share/ublue-os/justfile, and that in turn imports /usr/share/ublue-os/just/00-default.just, which contains a recipe called _default that does what j0rge descibes above, but that recipe doesn’t get executed as the default recipe in the installed version of just. After reviewing the just docs, it’s ambiguous to me whether this is correct behavior or a bug… the docs say that the default recipe is the first receipe, and bluefin’s _default is the first after processing imports, but perhaps the just dev meant the first recipe in the main justfile.
Edit: Oh, I see that there’s also a ujust command that behaves as described… this issue was discussed in this post. That makes sense, but given that the Bluefin announcment blog post uses plain just in its examples, this could continue confusing new users, at least until more getting started documentation is written. FWIW, I’d vote for sticking with the plain just command to avoid confusion, and just moving the default recipe into ~/.justfile if needed.