Little inconsistency on the subsystems docs page: it says you can use

./pants help $subsystem_name

right after subclassing

Subsystem

but that doesn't seem to work. It looks like you need to consume that subsystem in a registered rule for pants to pick it up. My guess would be you'd need a dummy or trival rule to make this work, but I don't know if that's a good recommendation

Oh good catch (Alternatively, you can say

SubsystemRule(MySubsystem)

(from pants.engine.rules), and ensure that’s included in the

rules()

entry point in

register.py

.

collect_rules()

will automatically set that up for you by inspecting the signature of your rules and seeing if they subclass

Subsystem

)