Does Modularity Coordinate? Disentangling Decoupling, Interfaces, and Design Rules via Simon’s Theory of the Artifact

Modularity undergirds every contemporary platform, yet the contestation of its coordinative capacity conflates complements with substitutes, either undermining app evolution or squandering coordination resources. Without guiding theory, platforms rely on costly trial and error. Drawing on Simon’s theory of the artifact, we disentangle modularity into three facets—decoupling (minimizing app-platform dependencies), interfaces (enabling app-platform integration), and “design rules” (circumscribing app internals)—theorizing that coordination complements the separability-fostering facets, while integration-fostering facets substitute for it. Design rules, ubiquitous in platforms yet theoretically overlooked, generate interpretive equivocality that coordination must resolve. Introducing design rules as modularity’s third facet—Simon’s missing “inner environment”—reveals coordination’s facet specificity. This helps platform owners to calibrate coordination, particularly at agentic artificial intelligence and hybrid platform frontiers.

History: Sam Ransbotham, Senior Editor.