1. Introduction to the chkpt Deterministic Execution Substrate

chkpt is a deterministic execution substrate for applying workflows that have been certified under an external governance model. It ensures that authorised workflows are executed predictably, remain within their defined behavioural boundaries, and produce complete, tamper‑resistant evidence suitable for institutional oversight and long‑term accountability.

1.1 Purpose

The purpose of chkpt is to provide a stable, predictable, and reviewable execution layer for certified workflows. chkpt does not define or certify workflows; instead, it enforces the execution‑side guarantees required to apply them faithfully. This separation ensures that governance and execution remain independent while enabling institutions to rely on deterministic behaviour, admissible behaviour enforcement, and durable evidence.

1.2 Scope

This specification defines the execution model, structural requirements, evidence obligations, and versioning rules that govern how chkpt applies certified workflows. It does not prescribe workflow content, governance processes, or domain‑specific policy. chkpt is designed to operate across diverse institutional environments without imposing assumptions about how workflows are authored, certified, or governed. These concepts are expanded in the Conceptual Model and Execution Model.

1.3 Role of chkpt

chkpt provides the execution guarantees required for institutions to trust that certified workflows are applied consistently. These guarantees include determinism, admissible behaviour enforcement, structural integrity, and the generation of tamper‑resistant evidence. By separating execution from governance, chkpt enables institutions to maintain control over workflow definitions while relying on a neutral substrate to apply them. Evidence requirements are detailed further in the Evidence Model.