watchOS

Build watchOS apps with Zylix using SwiftUI. This guide matches the current counter PoC implementation.

Platform status definitions follow the Compatibility Reference.

Status

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In Development — minimal counter implementation with C ABI bridge.

Prerequisites

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• macOS 13.0 or later
• Xcode 15.0 or later with watchOS SDK
• Zig 0.15.0 or later

# Verify installations
zig version
xcodebuild -version
xcrun simctl list devices | grep -i watch

Architecture Overview

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flowchart TB
    subgraph Watch["watchOS App"]
        subgraph WatchSwift["SwiftUI Layer"]
            WatchViews["Views"]
            WatchStore["ZylixBridge"]
            WatchBinding["C ABI"]
        end

        subgraph WatchZig["Zylix Core (libzylix.a)"]
            WatchVDOM["Virtual DOM"]
            WatchState["State Management"]
            WatchEvents["Event Handlers"]
        end

        WatchViews --> WatchStore
        WatchStore --> WatchBinding
        WatchBinding --> WatchZig
    end

    subgraph iOS["iOS Companion (optional)"]
        CompanionApp["Companion App"]
    end

Project Setup

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Step 1: Build Zylix Core for watchOS

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cd core

# For watchOS Simulator (recommended for development)
zig build watchos-sim

# For watchOS Device
zig build watchos

Outputs:

• Simulator: core/zig-out/watchos-simulator/libzylix.a
• Device: core/zig-out/watchos/libzylix.a

Step 2: Copy the Library

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cp core/zig-out/watchos-simulator/libzylix.a platforms/watchos/ZylixWatch/Libraries/

Step 3: Open the Xcode Project

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cd platforms/watchos
open ZylixWatch.xcodeproj

Step 4: Run

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Select a watchOS Simulator and run the ZylixWatch target.

Key Files

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• platforms/watchos/ZylixWatch/Sources/ZylixWatchApp.swift
• platforms/watchos/ZylixWatch/Sources/ContentView.swift
• platforms/watchos/ZylixWatch/Sources/ZylixBridge.swift
• platforms/watchos/ZylixWatch/Sources/Zylix-Bridging-Header.h

C ABI Functions Used

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Troubleshooting

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• undefined symbol: ensure libzylix.a is linked in the Xcode target.
• bridging header not found: verify the header path in Build Settings.

Tutorial

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For a full walkthrough, see the watchOS tutorial.