---
id: PLN-0106
ticket: real-render-worker-establishment
title: Migrate Desktop Host to Platform Services
status: open
created: 2026-06-06
completed:
ref_decisions: [DEC-0032]
tags: [host, desktop, platform]
---

## Objective

Move the desktop host from directly exposing `prometeu_drivers::Hardware` as the runtime bridge to owning a platform implementation.

## Background

The host currently creates `Hardware::new()` and passes it into firmware/runtime paths. `DEC-0032` requires hosts to implement platform services, not to expose a monolithic bridge.

## Scope

### Included

- Introduce desktop/local platform ownership in the host.
- Replace host usage of `Hardware::W/H` with platform display constants or framebuffer descriptor.
- Keep the same visual/audio/input behavior.

### Excluded

- Do not implement render worker thread.
- Do not change windowing library or presentation policy.

## Execution Steps

### Step 1 - Add host platform field

**What:** Host runner owns a platform implementation rather than raw `Hardware`.
**How:** Wrap current local driver implementation behind platform facades.
**File(s):** `crates/host/prometeu-host-desktop-winit/src/runner.rs`.

### Step 2 - Replace direct hardware constants

**What:** Stop reading `Hardware::W/H` directly in host rendering/input.
**How:** Use a framebuffer/display descriptor exposed by platform/render service.
**File(s):** `crates/host/prometeu-host-desktop-winit/src/runner.rs`, `input.rs`.

### Step 3 - Update debugger host setup

**What:** Debugger paths instantiate platform fixture/implementation.
**How:** Replace `Hardware::new()` in debugger setup.
**File(s):** `crates/host/prometeu-host-desktop-winit/src/debugger.rs`.

## Test Requirements

### Unit Tests

- Host crate tests compile.

### Integration Tests

- `cargo test -p prometeu-host-desktop-winit`.

### Manual Verification

- Desktop host still runs stress cartridge.

## Acceptance Criteria

- [ ] Desktop host owns platform services.
- [ ] Host no longer treats `Hardware` as runtime bridge.
- [ ] Display dimensions come from platform/render descriptor.

## Dependencies

- `PLN-0105`.

## Risks

- Desktop host mixes runtime and window concerns. Keep worker threading out of this plan.