---
title: UIX Decision & RFC Index
type: index
audience: human + agent
authority: navigational — the single entry point to the design/RFC corpus
status: current
related:
  canon: docs/CANON.md (semantic vocabulary)
  theming: src/uix/eidos/THEMING.md (eidos visual system, canonical reference)
---

# UIX Decision & RFC Index

This is the **entry point to the framework's design rationale** — the RFCs, the
per-subsystem design documents, and the decision logs. It is the E3 stratum of
the corpus: *why it is built the way it is*. Architecture (how the layers fit)
lives in [`src/uix/active_architecture.md`](../src/uix/active_architecture.md);
the semantic vocabulary lives in [`CANON.md`](./CANON.md); this file collects the
*decisions*.

Each entry gives the document, its status, and the one decision it records. Open
the document for the full argument — this index never copies it.

> **Naming note.** The filenames below are inconsistent (`*_ENGINE_RFC.md`,
> `*_RFC.md`, `DESIGN_*.md`, `DESIGN.md`). They are kept as-is on purpose: each
> name is cited as a provenance anchor in the source it governs (e.g.
> `// (DEPTH_ENGINE_RFC §5)` appears across `src/uix/eidos/lib/*.ts`, and
> `DESIGN_TIMR §12.8` across `src/arts/timer/*`). Renaming the files would drift
> ~30 of those citations. This index is the consistent surface; the filenames
> stay load-bearing. A physical rename is deferred until those citations are
> swept in the same pass.

---

## Eidos — expression channels (the 8 of the book)

[`CHANNELS_SYNTHESIS.md`](../src/uix/eidos/CHANNELS_SYNTHESIS.md) is the umbrella:
the conceptual synthesis of the book's eight expression channels (time · motion ·
presence · depth · shape · color · sound · haptic). The engine RFCs below take the
visual channels to reference-grade, one at a time, "breaking the model of the
references rather than copying it — with the cage open".

| RFC | Status | The decision it records |
| --- | --- | --- |
| [`COLOR_MODEL_RFC.md`](../src/uix/eidos/COLOR_MODEL_RFC.md) | RESUELTO (2026-06-02) — canon in THEMING §25 | The conceptual color model: rich palette (31 Radix scales) + hierarchy roles by explicit alias + intents auto-derived from the palette (identity = step 9). Rejected the "intent = single-anchor" variant. |
| [`COLOR_ENGINE_RFC.md`](../src/uix/eidos/COLOR_ENGINE_RFC.md) | PROPUESTA (2026-06-04) | The *physical* layer of color: OKLCH · P3 wide-gamut · APCA contrast · 1-seed generator. Changes how the color variables are produced, not which exist or what they mean. |
| [`TYPOGRAPHY_ENGINE_RFC.md`](../src/uix/eidos/TYPOGRAPHY_ENGINE_RFC.md) | PROPUESTA (2026-06-05) | Typography to reference-grade, additively behind the frozen token contract (audit → compare → extend, mirroring color). |
| [`DEPTH_ENGINE_RFC.md`](../src/uix/eidos/DEPTH_ENGINE_RFC.md) | Propuesta | The depth/presence channel: "depth is not something an element *has*, it is something that *happens*". Two-moment model (state + event). |
| [`SHAPE_ENGINE_RFC.md`](../src/uix/eidos/SHAPE_ENGINE_RFC.md) | Propuesta | The shape channel (the book's 8th and last expression channel) as orthogonal axes on top of the untouched `--radius-*` magnitude. |

## Eidos — structural systems

| RFC | Status | The decision it records |
| --- | --- | --- |
| [`STRUCTURE_ENGINE_RFC.md`](../src/uix/eidos/STRUCTURE_ENGINE_RFC.md) | Propuesta | Space · density · scale as state-only structural systems (the stage, not the event): rhythm, fluidity, axis composition under the open cage. |
| [`SCALING_RFC.md`](../src/uix/eidos/SCALING_RFC.md) | ✅ IMPLEMENTADO (2026-06-02) | Splits global zoom (`scaling`: 90/95/100/105/110) from density. Scales space + control-height + font-size + icon-size; radius/border/shadow/line-height excluded on purpose. |

## Arts — subsystem design documents

Exhaustive design-and-implementation records for the harder runtime artifacts.
Each predates the 2026-05-14 directory-rename sweep and carries a historical-note
header about the old short names (`conn`/`timr`/`sess`).

| Document | Subsystem | The decision it records |
| --- | --- | --- |
| [`DESIGN_CONN.md`](../src/arts/connection/DESIGN_CONN.md) | `connection` | Realtime connection registry: transports, reconnect, heartbeat, request/reply, channels, session bridge. |
| [`DESIGN_TIMR.md`](../src/arts/timer/DESIGN_TIMR.md) | `timer` | Deterministic timer scheduler: clock injection, the race-safety contract (§12.8), one-shots, intervals, backoff. |
| [`DESIGN.md`](../src/arts/session/DESIGN.md) | `session` | Session lifecycle consultation: adopt/revoke/refresh, profile loading, SSR via cookie reader. |

## Cross-cutting decision logs

| Document | The decision it records |
| --- | --- |
| [`LIBRO_VARIACIONES_Y_EXTENSIONES.md`](../src/docs/LIBRO_VARIACIONES_Y_EXTENSIONES.md) | The running log of where the implementation deviates from (or extends) the book's editorial canon — verbs, adoptions, clusters, and the D.x architectural decisions. The seed for a consolidated decision-log. |
| [`GESTURES.md`](../src/uix/soma/layers/gesture/GESTURES.md) | The soma gesture layer design: `Gesture.base`/`drag`/`resize`, velocity ring-buffer, axis lock, deferred pointer capture. |
| [`active_architecture.md` §7 + `arts/adom`/`arts/perf` READMEs](../src/uix/active_architecture.md) | **Sec-dom — read-timing & token-resolution (2026-06-29).** The framework governs layout READS like it governs writes: `dom.measure` (coalesced post-layout reads), `eidos.resolveToken` (token→colour in JS, no `getComputedStyle` probe), the discoverable `uix.color`/`uix.perf` surfaces. Decided: **reject** a static grep-guard (too noisy across ~120 legit reads, and it can't catch the sync-read-after-write *ordering* nor cover routes) — the dev `uix.perf` detector (Long Animation Frames) is the runtime safety net instead. |