A structural pattern for Legible Modular software (arxiv.org)

Researchers propose a new structural pattern—“concepts and synchronizations”—to make software more legible and modular for a world where LLMs increasingly write and modify code. They argue current codebases are often “illegible”: behavior isn’t directly traceable to code, and modules aren’t cleanly separable, which undermines three engineering goals: incrementality (small localized changes), integrity (avoiding regressions), and transparency (clear build‑time diffs and runtime traceability). The pattern separates fully independent services (concepts) from event‑based rules (synchronizations) that mediate behavior; those rules are expressed in a small domain‑specific language (DSL) so behavioral features become granular, declarative artifacts that are easy to generate, reason about, and evolve. Technically, this decoupling means behavioral glue is represented as explicit, event-driven synchronizations rather than hidden control flow inside services, improving observability and reducing coupling. The DSL lets LLMs produce focused synchronization rules instead of large service rewrites, which aids incremental delivery, automated testing, and verification. A RealWorld benchmark case study illustrates gains in modularity and legibility, suggesting the approach can reduce accidental breakage and make runtime actions easier to audit—practical advances for teams using AI-assisted coding and for tooling that needs clear, machine‑friendly behavioral specifications.