# Substance — `architecture/stack` **Output path:** `{kbFolder}/architecture/stack.md` **Topic focus:** the technology stack — languages and their versions, frameworks and major libraries, the runtime/interpreter, package manager, and the build toolchain. Describe *what the project is built with*, not how it is deployed. **Discovery input to read:** the `stack` domain findings from Phase 1 (languages, dependency manifests, lockfiles, runtime versions). Cross-reference the `testing` findings only for the test-runner dependency. **Required output:** - Confidence header on line 1. - A languages/versions table or list (each fact `[?]`-marked if not directly observed). - Frameworks & major libraries with their roles. - Runtime + package manager + build tool. - No deployment, routing, or schema content — those are other docs. **Not applicable:** if the project has no identifiable stack (e.g. an empty or docs-only repo), the topic is *absent* — a certainty, not a low-confidence guess. Write a **confident** not-applicable stub: line 1 is ``, then the `# Stack` heading and the one-sentence absence statement `No application stack detected — this repository contains no build- or runtime-bearing sources.` Do NOT lower confidence — an absent topic is known with certainty.