Software art is characterised by a close concern with the culture of software and the medium of programming. This inevitably demands an engagement with the terrain of the instrumental; software is a sphere of tool-making and programming is governed by conceptions of functional (and generic) utility. Yet where does this leave art? If, in Kantian terms, art is defined by its uselessness (by its lack of any externally grounded necessity) and if, in classical critical theoretical terms, this alienation from function opens up a space of critique, then how can art explore and participate within the instrumental without abandoning its fragile critical autonomy? This paper addresses this question, drawing upon Heideggers conception of technology and Platos conception of poesis to argue that critical software art can not simply oppose the instrumental character of software; instead it must acknowledge its own complicity in the operations of hiding and unreflective functioning that characterize the instrumental once the latter is re-conceived apart from the simplicity of human agency and humanly determinable ends. I examine one of my own software projects as a means of clarifying the dilemmas of critical aesthetic purchase that emerge as a result of this engagement with the instrumental dimension of software.