Prototypes a stage-based toolchain bootstrap with transitions using "quux-lang" — a fictitious language — as an example.
❯ bazel cquery 'filter("^//:*", deps(:foo) - filter("//:_quux_toolchain_current_bootstrap_stage_is_[0-9]*", //:*)) - //:defs.bzl - //:toolchain - //:quux_toolchain_type' --output=graph > out.dot