Show HN: UPA – An explicit organizational model for humans and AI A developer released UPA (Unified Process Architecture), an open-source experiment that represents an organization's business rules, workflows, systems, evidence, assumptions and unknowns in a shared machine-readable structure that humans and AI agents can inspect together. UPA uses the Z3 theorem prover to formally check selected properties of the model, trace rules back to their evidence, and explore change impact, with a demonstration model built on the eShopOnWeb sample application. The project states it "cannot prove that the model is reality," verifying only properties under declared assumptions and never reporting UNKNOWN as success, and requires Python 3.11 or later plus z3-solver and pytest. ██╗ ██╗ ██████╗ █████╗ ██║ ██║ ██╔══██╗ ██╔══██╗ ██║ ██║ ██████╔╝ ███████║ ██║ ██║ ██╔═══╝ ██╔══██║ ╚██████╔╝ ██║ ██║ ██║ ╚═════╝ ╚═╝ ╚═╝ ╚═╝ ─── AN EXPLICIT ORGANIZATIONAL MODEL ─── PROBABILISTIC AI ─────────────► UPA ─────────────► DETERMINISTIC ORG RULES If AI agents increasingly build and operate software, where does the organization itself live? Its business rules are scattered across code, documentation, tickets, APIs, workflows, databases, and people's heads. AI can search those sources, but searching is not the same as having an explicit model of how the organization works. UPA is an experiment in making that model explicit. It represents business rules, workflows, systems, evidence, assumptions, and unknowns in a shared machine-readable structure that humans and AI agents can inspect together. UPA can then formally check selected properties of that model with Z3, trace rules back to their evidence, explore change impact, and use the model as context for AI-assisted work. UPA is not trying to replace code, documentation, or people. It is trying to make the organizational knowledge behind them explicit. Think of it as an experiment towards a machine-readable organizational brain. See it first: open the eShopOnWeb viewer https://julianfromano.github.io/upa-organization-brain/ narrative · build and verify a checkout model quick-start · read how the UPA skill works https://github.com/julianfromano/upa-organization-brain/blob/master/skills/upa-generate/SKILL.md . | The customer journey as connected behavior. Open the narrative https://julianfromano.github.io/upa-organization-brain/ narrative . | Explore reusable components, down to individual behaviors and rules. Open the hierarchy https://julianfromano.github.io/upa-organization-brain/ levels . | Unlike a document dump or a chatbot trained on disconnected prose, a UPA model connects workflows, reusable rules, systems, evidence, and assumptions in one traceable structure. People and AI can inspect the same context, check modeled rules, and use its machine-readable artifacts in viewers, generators, and tests—while people remain responsible for validating evidence and approving changes. What happens when a customer signs in with an anonymous basket already in progress—what happens to it? The answer is usually implicit in several places at once: application code · documentation · database constraints · API behavior · product decisions UPA turns that distributed knowledge into something explicit. The sketch below is conceptual , not UPA syntax: RULE: on sign-in, the anonymous basket is merged into the customer's basket EVIDENCE: BasketService.cs: