Nexus

A SwiftUI iOS banking demo focused on cards and their features — card issuing, freeze/unfreeze, report lost/stolen, replacement tracking, spending limits, live balances, and transaction history with search and filtering. Ships with a full demo mode so the whole v1.0 feature set runs with no backend.

• Stack: Swift 6 language mode (swift-tools-version: 6.3), Xcode 26.6 (CI pin), iOS 17.0+.
• Architecture: MV (Model-View) — @MainActor @Observable models drive SwiftUI views through explicit viewState enums. No ViewModels, no Combine, no completion handlers.
• Packages: three SPM packages under AppPackages/ (NexusDomain — entities, protocols, one AppError; NexusData — session, data sources, repositories, persistence, logging, #if DEBUG mocks; NexusFeatures — design tokens, shared UI, navigation, screens) plus a thin Nexus app target that composes them.
• Localization: English, Estonian, Russian via one app String Catalog.
• Persistence (live mode): SwiftData for durable state, Keychain for credentials, display-safe logging only (last four digits, never PANs).

Requirements

• Xcode 26.6 with the iOS 26.5 SDK and an iPhone 17 simulator (tests target it by name). That's the CI pin — local development may use a newer Xcode (e.g. 27), so a change must build on both.
• SwiftFormat + SwiftLint on PATH for the formatting/lint gate, pinned to swiftformat 0.63.0 and swiftlint 0.65.1 (see Brewfile).
• Optional: activate the pre-commit hook with git config core.hooksPath .githooks.

Run

Open Nexus.xcworkspace and run the Nexus Demo scheme on an iPhone 17 simulator. Demo mode (-demoMode, also selected by API_ENVIRONMENT = demo) builds an in-memory mock graph — no network, Keychain, or disk — with seeded cards, offers, balances and transactions, and a Reset demo action in the UI. Release builds compile the demo graph out and ignore -demoMode; live mode composes the real data layer and reports the missing-backend config gap while API_BASE_URL is empty.

UI tests additionally understand -demoState, -demoActionState, and -demoOpenCard launch knobs (parsed in Nexus/AppContainer+Dependencies+Demo.swift).

Test

The workspace TestPlan aggregates the unit, integration, and UI suites:

xcodebuild test -workspace Nexus.xcworkspace -scheme Nexus \
  -destination 'platform=iOS Simulator,name=iPhone 17'

UI tests launch the app in -demoMode; the localization canaries launch with -AppleLanguages (ru) / (et) and assert translated chrome on the real view layer. The first test build after a fresh DerivedData prints known Xcode dependency-scan warnings — documented one-time tooling noise, not a failure (see Documentation/AGENTS.md).

Layout

Nexus.xcworkspace          workspace (open this)
AppPackages/NexusDomain/   domain: entities, repository/service protocols
AppPackages/NexusData/     data: session, sources, repositories, mocks
AppPackages/NexusFeatures/ features: design tokens, shared UI, screens
Nexus/                     thin app target (composition root, demo wiring)
NexusTests/                app-target unit tests (AppContainer, smoke)
NexusUITests/              UI suites (dashboard, card detail, transactions)
Configs/                   Debug/Release xcconfigs + Info.plist
scripts/                   format/lint wrappers (format.sh, lint.sh)
TestPlan.xctestplan        workspace test plan (every suite)
Brewfile                   Homebrew manifest: swiftformat + swiftlint
Documentation/             operating guide, architecture, styleguide, spec, roadmap

Documentation

Start at Documentation/AGENTS.md — the operating guide, whose doc map and authority chain (§8) route every task to the right file. Highlights: architecture.md (blueprint; §14 is the one-paragraph summary), spec.md (product scope + per-feature behavior), styleguide.md (Swift style), ROADMAP.md (release framing, decision log, milestone log), CONTRIBUTING.md (commits/PRs).

Scope notes

v1.0 ships demo-first with no backend. Payments, biometrics/app lock, Apple Pay provisioning, alerts/insights and additional locales are deferred beyond v1.0; demo and server content stays English by design.