Summary

Windows users who prefer WSL for their development environment currently cannot use the Desktop app effectively. The Desktop app only spawns a native Windows sidecar binary, but many developers have their projects and tooling inside WSL.

Current Behavior

The Tauri desktop app spawns OpenCode as a native Windows binary via the sidecar mechanism:

• packages/tauri/src-tauri/src/lib.rs:64-91 - spawn_sidecar() always uses native binary
• packages/tauri/scripts/utils.ts:3-24 - Only defines native platform targets

Proposed Solutions

Option A: Settings Toggle (Recommended)

Add a settings UI that allows users to choose their backend:

1. Native (default) - Use bundled sidecar binary
2. WSL - Run wsl -e opencode serve --port=PORT
3. Custom command - Power users specify their own command

The setting would persist in app config and be read at startup.

Implementation:

• Enable the currently disabled Settings button in layout.tsx:536-546
• Add settings modal with backend configuration
• Modify spawn_sidecar() to check config and use appropriate spawn method
• For WSL: use Command::new("wsl").args(["-e", "opencode", "serve", ...]) instead of sidecar

Option B: Auto-Detection

Detect if the opened project folder is inside WSL (path starts with \\wsl$\ or /mnt/) and automatically use WSL backend for those projects.

Pros: Zero configuration
Cons: May not match user intent, harder to implement reliably

Option C: Environment Variable Override

Support OPENCODE_BACKEND=wsl environment variable that changes spawn behavior.

Pros: Simple implementation
Cons: Not user-friendly, requires launching from terminal

Additional Context

Related WSL issues (different problems):

• /editor: non-successful editor exits should keep the text in the textarea #693 - TUI rendering in WSL
• fix: Copilot Premium Requests #595 - Paste issues in WSL terminal

This issue is specifically about the Desktop app being able to launch the OpenCode server via WSL rather than native Windows.

Use Case

1. User has projects inside WSL filesystem
2. User installs OpenCode Desktop on Windows
3. User wants Desktop UI but with OpenCode running inside WSL (for proper file access, tooling, etc.)