ABSTRACT — ELYON-SOL Modern software systems increasingly operate in environments where correctness alone is insufficient to ensure safe or valid outcomes. Systems may produce logically consistent and policy-compliant results while still entering states that cannot be legitimately resolved by users. This paper introduces Elyon-Sol, a governance-layer system architecture that enforces pre-execution eligibility constraints prior to policy evaluation and execution. Elyon-Sol formalizes a deterministic eligibility boundary based on four conditions: consent, authority, coverage, and presence. Requests that fail to satisfy these conditions are terminated before execution, preventing continuation into invalid or unresolvable states. This establishes a fail-closed model in which system behavior is governed by the existence of a legitimate path forward, rather than by post hoc validation or corrective handling. The architecture is positioned upstream of policy engines and execution layers, operating as a non-executing decision surface that evaluates whether action should be permitted at all. This separation distinguishes eligibility from policy and execution, ensuring that downstream systems are invoked only when preconditions are satisfied. The approach addresses a class of system failures characterized not by incorrect outputs, but by the persistence of interactions that lack valid resolution. The design is validated through real-world interaction case studies across healthcare, finance, and insurance domains, demonstrating consistent patterns of unresolvable system states and continuation without legitimate outcomes. Elyon-Sol prevents these conditions by enforcing deterministic refusal semantics, providing an auditable and reproducible mechanism for governing system behavior prior to action. This work contributes a system-level approach to software governance that prioritizes resolvability as a prerequisite for execution, offering a framework for designing systems that fail safely and terminate when legitimate completion is not possible.
Justin LaPorte (Tue,) studied this question.