This article brings Friedrich Kittler’s media determinism to bear on a selection of works from Brian O’Nolan’s oeuvre. It briefly examines Myles na gCopaleen’s play with posthuman hybrids in Cruiskeen Lawn, seeing his vignettes as extravagant, humorous depictions of the ways our bodies and symbolic order are determined by the mechanical. It then maps the movement between typed and handwritten texts in At Swim-Two-Birds, considering the progression between modes of inscription as a commentary on modernity, meaning, and presence. Despite At Swim-Two-Birds’s overt commitment to the typewriter’s mode of impersonal, mechanical assemblage, we find, at the novel’s core, inscriptions that are invested in the personal and immediate, and which are driven by intention. The novel’s modernist detachment and technological investments are underpinned by nostalgic desires, ironically and earnestly presented, for the immediacy and presence of more traditional relations with language and the text. By tracing the implications of the writing implements used by the various authors in At Swim-Two-Birds, we uncover a new aspect of the novel’s mediation between modernity and tradition.