System migration

Change what runs underneath while the business keeps running. A rewrite fails when it stops the product for months, when nobody can tell whether the new code behaves like the old, or when the knowledge in the old system leaves with the people who wrote it. Every rule below exists to prevent one of those.

Apply only the routes and checks for the selected job. Read a linked skill's named file from its installed folder when available, or from the linked source. Report an unavailable required reference instead of inventing it. [skill-authoring, DISTRIBUTION.md#composing-skills]

Incremental ports (new language, runtime or framework)