# Shade V2.2 — Feature plan: product, platform, and developer experience

**Status:** Done — superseded by V3.6 (inbox), V3.7 (bridge), V3.8
(workers), V3.9 (file metadata), V3.10 (recovery), V3.12 (KT). All
landed in the 4.0 GA release; see [`docs/ROADMAP.md`](../ROADMAP.md).

This document gathers **planned features** that extend Shade beyond today’s core (X3DH + Double Ratchet + Streams/transfer): groups, asynchronous delivery, richer file UX, web workers, CLI, API docs, and scaffolding.

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## 1. Groups / multiple participants

**Vision:** Beyond strict 1:1 — multiple identities in the same “conversation” or shared context (messages and possibly shared file/stream policy).

**Challenges:**

- Today’s Signal-like core is naturally 1:1; groups need either **pairwise sessions per member**, **sender keys / fan-out**, or a **dedicated group protocol** (larger architectural step).
- Lifecycle: invites, member removal, compromised device, history, and group PCS.

**Goals for early milestones (proposal):**

1. **Document** a recommended pattern for “group-lite” (e.g. coordinator relays ciphertext without decrypting + clients encrypt per-recipient).
2. **Optional** minimal API making fan-out easier in the SDK (without promising full MLS).

**Acceptance criteria (MVP definition):** Explicit scope in docs + one reference architecture; no ambiguous “group is done” without an updated threat model.

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## 2. Async store-and-forward messaging

**Vision:** Recipient need not be online; **ciphertext** is stored temporarily and fetched when the recipient returns — the server never sees plaintext.

**Distinction from the prekey server:**

- Prekey stays **public keys only** (or extended only under strict policy).
- A **dedicated relay/inbox service** (or app-owned backend) holds **encrypted blobs only** with TTL, idempotency, and authorization (who may list/fetch).

**Deliverables (proposal):**

- Protocol sketch: address registration, `PUT` blob, `GET`/`DELETE` or lease, replay protection at the application layer.
- SDK helpers: outgoing queue, poll/pull, or push-notification hook (without dictating mobile platform).

**Acceptance criteria:** Threat-model section “what the relay sees” + reference implementation or example app.

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## 3. File metadata and preview

**Vision:** Richer UX **without** leaking sensitive content to the server: filename, MIME type, length where known; **optional** client-generated thumbnails or previews encrypted as separate blocks or small payloads on the control init path.

**Technical considerations:**

- Anything sent must be **E2EE** or omitted; plaintext metadata on the server must be deliberate and minimal.
- Thumbnails should use **format hardening** on the client (size limits, sandboxing in UI).

**Acceptance criteria:** Extended `stream-init` (or sidecar envelope) with optional fields + widget support for “preview when available”.

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## 4. Web: worker-based crypto and streaming

**Vision:** Large files in the browser without blocking the main thread or blowing RAM — **Web Crypto / noble** inside a **Worker**, **ReadableStream/WritableStream** end-to-end chunk pipeline aligned with `@shade/streams` / transfer.

**Deliverables:**

- `@shade/crypto-web` (or companion) patterns: transferable buffers, lifecycle, errors surfaced to the UI.
- Documented constraints (Safari, chunk sizing, Service Worker vs dedicated worker).

**Acceptance criteria:** E2E demo or test that sends multi‑MiB through a worker without a blocking UI.

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## 5. CLI: `shade doctor`

**Vision:** One command that **diagnoses the environment** before production debugging.

**Typical checks (proposal):**

- Reachability of `prekeyServer` (`/health`, optional OpenAPI).
- Local config: storage path, rotation headers, clock skew (relevant for signed requests).
- **Streams:** transfer routes mounted, auth matches expected key, `GET .../state` behaves as expected in test mode.
- CLI / Node/Bun runtime versions and `@shade/*` packages where readable from `package.json`.

**Acceptance criteria:** `shade doctor` with exit codes suitable for CI (warn vs fail).

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## 6. OpenAPI / docs

**Vision:** All HTTP contracts teams are expected to implement (prekey **and** transfer) appear in **one** OpenAPI story or clearly linked specs — not only README examples.

**Deliverables:**

- Consolidate or cross-reference `openapi.yaml` with transfer endpoints (`/v1/transfer/*`) and security schemes for chunk upload.
- `/docs` (Redoc or similar) or published static artifacts for versioned specs.

**Acceptance criteria:** Generated client (e.g. Python/Go) from spec without manual fixes for the happy path.

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## 7. `shade init`

**Vision:** Scaffolding from **empty repo** to a **minimal runnable** app with Shade and optional streams.

**Extensions:**

- New or extended template: **minimal Hono/Fastify** app with `Shade.transferRoute()` mounted, auth example matching the SDK authenticator, `.env` template.
- Optional: demo `shade doctor` after init.

**Acceptance criteria:** `shade init …` produces a project that `bun install && bun run start` runs with documented env vars.

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## Dependencies between items

```text
shade init ─────► doctor (same conventions for URLs and secrets)
openapi/docs ◄── transfer + prekey (single source)
web workers ───► streams UX (large file in browser)
groups ◄──────── store-and-forward (often related socially/technically)
metadata/preview► widgets + proto/control plane
```

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## Document versioning

- **V2.2** — feature backlog as described. Split into issues/ADR per feature when implementation starts.
