Phil Mayers wrote:

I'm putting together some glue-ware for a system, and would like to hide the underlying nature of it. It's a bit of software that fits in and around routers / switches etc. and there's a pretty common CLI for those these days, which consists of a hierarchial context-based set of commands, plus completion, e.g. on Cisco, although I suspect everyone is familiar with the concept: ... Any such beast exist?

Have a look at twisted.python.usage's idea of subCommands, that should help. You need to build tab completion etc. on top of that; but ideally, t.p.usage will allow you to have the same thing available straight from shell: $ mycommand sub1 --option=42 sub2 -f sub3 Doing stuff... or $ mycommand your-app-here> sub1 --option=42 sub1> sub2 -f sub1 sub2> sub3 Doing stuff... sub1 sub2> Additionally, this snippet allows you to implement the subcommand modularly, with twisted's plugin architecture. --8<-- from twisted.python import usage, plugin class SubCommandOptions(usage.Options): def __init__(self): usage.Options.__init__(self) self.subCommands = [] plugins = plugin.getPlugIns('YourApplicationNameHere-command') plugins.sort() for p in plugins: module = p.load() description = getattr(p, 'description', None) self.subCommands.append((p.name, None, getattr(module, 'Command'), description)) self.subCommands.sort() def postOptions(self): if not hasattr(self, 'subOptions'): self.opt_help() --8<-- --8<-- # plugins.tml register( type="YourApplicationNameHere-command", module="YourApp.commands.sub1", name="sub1", description="Frobble the kibits", ) --8<-- --8<-- # YourApp/commands/sub1.py from twisted.python import usage class Command(usage.Options): def postOptions(self): do_stuff_here() --8<--