ONE SOURCE OF TRUTH, THREE LENSES — every UI feature exists on Web, Mac and PC (Aristide 2026-09-01)

kerfmaster pin list · UI / workflow decisions

rulingA decision by Aristide or Jordan. True because it was decided; it can be superseded, but it cannot be stale.

Content last changed 2026-09-01 — computed from the item itself, not typed.

Source (Aristide, 2026-09-01): "ok. one big last rule for the UI. We need to have one source of truth, always. when we ask for a feature or button, it needs to be developed for all versions: Web or mac or PC. So it needs to be looked at through all 3 lenses, always. so do not develop a feature for the web version, that later can't be also created for the PC and vice versa. Same for Mac vs web."

What it binds

One source of truth — feature logic, table values, defaults and override records live ONCE (the engine + JSON data model); the Web, Mac and PC shells are renderers over the same state, never parallel implementations that can drift. This is the interface-scale form of the client/shop-sheet 'one dataset, two renderers' discipline and of 'data in JSON, generator separate from presentation, no hand-edited HTML'.
Three-lens design gate — every requested feature or button is evaluated for Web AND Mac AND PC before it is built for any of them. A capability only one platform offers (a browser-only API, an OS-only control) must not become the feature's foundation; find the form all three can carry or flag the conflict to Aristide/Jordan before building.
Parity is a requirement, not a roadmap — 'developed for all versions' means a feature ships everywhere it can be operated, not web-first with native 'later'.

Why the existing discipline already serves it

Every UI-bound decision so far is recorded as data + an engine seam (per-contour tooling docs, overrides_from, rules.check_drag, nest_rules one-click slots, part-list columns): a platform shell drives those seams; none of them assume a rendering technology. Keeping new work in that shape is how this ruling stays cheap to honour.