Intrada

A practice notebook for musicians: build a session from your library, play it through with a timer and rep counting, and score how it went (Plan, Practice, Track).

Two native apps on one Rust core (Crux), kept at parity: SwiftUI for iPhone in ios/ and Compose for Android in android/. Both are offline-first: on-device SQLite is the source of truth, and neither needs a network or an account. The core owns all logic; each app renders its view model and fulfils effects.

Read next: CLAUDE.md for the rules, docs/roadmap.md for direction, just status for what is in flight, SETUP.md for accounts and secrets, and docs/reference.md for the mechanics. just --list lists the commands.

Prerequisites

Everyone

• Rust via rustup, pinned in rust-toolchain.toml. Not Homebrew's Rust, whose cargo shadows rustup and has no mobile targets
• mise, then mise install, for everything mise.toml pins (just, xcodegen, cargo-nextest, Ruby, cargo-swift 0.9.0 and more)
• gh, signed in with gh auth login, and jq
• worktrunk (brew install worktrunk); its config is in docs/worktrees.md
• Optional: cargo-deny and gitleaks, which just check skips when missing

iPhone

• Xcode 26+ with the iOS Simulator runtime
• rustup target add aarch64-apple-ios aarch64-apple-ios-sim x86_64-apple-ios

Android

• Android Studio; the recipes use its JDK and ~/Library/Android/sdk when JAVA_HOME and ANDROID_HOME are unset
• From the SDK Manager: Command-line Tools, the Emulator, Platform Tools, the SDK Platform and Build Tools the android job in .github/workflows/ci.yml installs, the NDK pinned as intrada.ndkVersion in android/gradle.properties, and the Android 36 Google APIs arm64 image
• cargo install cargo-ndk --version 4.1.2 and rustup target add aarch64-linux-android x86_64-linux-android
• just android-gen once, to build the bindings

Agent tooling (optional)

• The Claude Code plugins rust-analyzer-lsp, swift-lsp and kotlin-lsp, plus brew install xcode-build-server and brew install --cask kotlin-lsp, then just lsp-setup; see code intelligence in docs/working-with-agents.md
• graphify (uv tool install graphifyy); see docs/reference.md
• rtk (brew install rtk, then rtk init -g --hook-only --auto-patch), which shortens command output

Git hooks install in Claude Code sessions; elsewhere run bash scripts/install-git-hooks.sh once. Forking: set your Apple Team ID in ios/project.yml.

Quick start

just ios          # regenerates the Swift bindings if the core changed, then opens Xcode
just android-run  # regenerates the Android bindings, boots the emulator, installs and screenshots

All rights reserved. See LICENSE.