Pucky

Offline vibe coder for your iPhone using Gemma 4 and Oxc.

Describe an app in chat, watch Gemma 4 edit a single TSX or TS file on-device, and see the result render live in an embedded WKWebView — no network, no Metro, no Expo, no laptop.

What's inside

• Native SwiftUI host — three tabs (Code, Chat, Preview), dark theme, iPhone 17 Pro only.
• Gemma 4 E2B via Gemma4SwiftCore on an MLX GPU backend. Streaming tool calls drive a edit_code / replace_code loop against one editable file.
• Oxc in Rust (rust/oxc-bridge) — a staticlib shipped as OxcBridge.xcframework that parses, type-strips, and transforms TS/TSX to ES modules at keystroke speed.
• In-app preview runtime — a hand-rolled React / React Native shim (View, Text, Pressable, ScrollView, TextInput, StyleSheet, Flexbox, hooks) plus a Three.js template, both loaded into WKWebView via import maps. Zero Node, zero bundler.

Templates

• App (React Native) — imports from react / react-native, default-exports a root component.
• 3D (Three.js) — imports three, default-exports setup(canvas) with a teardown callback.

Both templates expose exactly one editable file to the model, so Gemma 4 never has to invent paths or juggle a filesystem.

Build

xcodegen generate
xcodebuild -project Pucky.xcodeproj -scheme Pucky \
  -sdk iphonesimulator \
  -destination 'platform=iOS Simulator,name=iPhone 17 Pro' build

Requires Xcode 26.4 and the iOS 26.0 SDK. The Rust bridge is rebuilt with rust/oxc-bridge/build-ios.sh.