Nutri-E Architecture

Nutri-E is a supplement tracking app built with SwiftUI (iOS) and Jetpack Compose (Android). It provides intelligent supplement management, dose tracking, nutrient analysis, and AI-powered food analysis.

Tech Stack

Platform	Technology
iOS	SwiftUI, Core Data, StoreKit 2, iOS 16+
Android	Jetpack Compose, Room, Kotlin
Backend	Cloudflare Workers (3 workers)
AI	GPT-4 Vision via Cloudflare Worker proxy

Architecture Pattern

MVVM with a Service Layer:

flowchart TB
    subgraph ios["iOS App"]
        views["SwiftUI Views<br/>(TodayView, SupplementsView, etc.)"]
        services["Services<br/>(SupplementService, OpenAIService, etc.)"]
        coredata["Core Data<br/>(Local persistence)"]
        models["Models<br/>(UnitType, Frequency)"]
    end

    subgraph backend["Cloudflare Workers"]
        openai["OpenAI Worker<br/>(GPT-4 Vision proxy)"]
        dsld["DSLD Worker<br/>(NIH supplement DB)"]
        apple["Apple Webhook Worker<br/>(Subscription lifecycle)"]
    end

    views --> services
    services --> coredata
    services --> models
    services --> openai
    services --> dsld
    coredata --> models

Layer	Implementation	Responsibility
Views	SwiftUI Views	UI rendering, user input
Services	Singletons (.shared)	Business logic, API calls
Persistence	Core Data	Local storage
Models	Core Data entities, enums	Data structures

Project Structure

ios/Nutri-E/Nutri-E/
├── Nutri_EApp.swift              # App entry point
├── ContentView.swift             # 5-tab navigation hub
├── Persistence.swift             # Core Data stack
├── Nutri_E.xcdatamodeld/         # Core Data models
├── Models/
│   ├── UnitType.swift            # Unit system
│   └── Frequency.swift           # Dose frequencies
├── Services/
│   ├── SupplementService.swift   # Core supplement operations
│   ├── DSLDSearchService.swift   # NIH database integration
│   ├── OpenAIService.swift       # GPT-4 Vision analysis
│   ├── DeviceAuthService.swift   # API security
│   └── StoreKitManager.swift     # In-app purchases
└── Views/
    ├── TodayView.swift           # Daily dashboard
    ├── SupplementsView.swift     # Supplement list
    ├── ScheduleManagementView.swift
    ├── NutrientsView.swift       # Nutrient tracking
    ├── MoreView.swift            # Settings
    └── FoodView.swift            # AI food analysis

Platform Strategy

iOS is the master platform:

1. All new features are implemented on iOS first
2. iOS serves as the reference for functionality, UX, and business logic
3. After iOS testing, features are ported to Android
4. Feature parity is maintained between platforms

Backend Workers

Worker	Purpose	Production URL
OpenAI	GPT-4 Vision for food/supplement analysis	nutrie-openai-worker-v2.invotekas.workers.dev
DSLD	NIH supplement database proxy	nutrie-dsld-worker-v2.invotekas.workers.dev
Apple Webhook	App Store subscription lifecycle	nutrie-apple-webhook-worker-v2.invotekas.workers.dev

All workers support multi-environment deployment (production + sandbox) and use device authentication (HMAC-SHA256).

Brand Mascots

Character	Color	Role
Nutri-E	Purple	Health Expert -- nutrition guide
Cuti-E	Pink	Support Specialist -- user engagement
Codi-E	Teal	Tech Wizard -- AI features

Design Principles

• Card-based UI with consistent spacing and corner radius
• Explicit UI -- all functionality through visible controls, no hidden gestures
• Offline-First -- Core Data for local persistence, works without network
• KISS -- minimal abstraction, direct Core Data access via @FetchRequest