<craft name="stairs">
	<parameter name="numberOfSteps" type="int" default="5"/>
	<script type="text/openjscad">
		function main(params)
		{
			var steps = params.numberOfSteps || 5;

		    if(steps <= 0) steps = 5;
		    
		    var c = cube();

		    for(var i = 0; i < steps; i++){
		        c = union(c,cube().translate([i,0,0]).scale([1,1,i+1]));
		    }

		    return c;
	    }
	</script>
</craft>