Smart Stairs is a command -type plugin and can be accessed from the 'Plugins' menu.
Each instance of Smart Stair can serve as a stand-alone stair, but Smart Stair also supports handling multiple stairs as one by nesting instances within each other - see -> working with multiple stairs .
Note:
Smart Stairs
generates an internal hierarchy of parametric- and instance- objects, so you
can also just collapse it and use the result as a starting point
to build upon.