EchoLedger

A personal finance tracking iOS app built as a school project. The primary goal is learning and applying Clean Architecture with a UseCase pattern, local persistence via SwiftData, and remote storage via Firebase.

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Tech Stack

Component	Technology
Language	Swift 6
UI	SwiftUI (iOS 18+)
Observability	@Observable (not ObservableObject)
Local persistence	SwiftData
Remote backend	Firebase Auth + Firestore
Dependency injection	DIContainer
Navigation	AppCoordinator

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Architecture

The project follows a strict Clean Architecture with clear layer separation:

Domain
└── Entities (Transaction, Account, Institution, User)
└── UseCases (AddTransaction, GetAccounts, ArchiveAccount, ...)
└── Protocols (-Providing)

Data
└── Local (SwiftData — -LocalSource, -Model)
└── Remote (Firebase — -RemoteSource, -Remote)
└── Storings (-Storing, implements -Providing)

Presentation
└── ViewModels (@Observable, @MainActor)
└── Views (SwiftUI)
└── Subviews (SplitRowView, AccountRowView, ...)

App
└── DIContainer (single source of truth for DI)
└── AppCoordinator (navigation + ViewModel ownership)

Naming Conventions

Pattern	Example
Protocol	TransactionProviding
Implementation	TransactionStoring
Local source	TransactionLocalSource
Remote source	TransactionRemoteSource
Remote struct	TransactionRemote
UseCase input	AddTransactionInput

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Domain Model

Core Entities

• User — application user
• Institution — financial institution (bank, insurance, etc.)
• Account — bank account linked to an institution, archivable
• Transaction — financial operation with amount distribution across multiple accounts via TransactionSplit

Key Business Rules

• Account balances are computed on demand (not stored)
• Accounts cannot be deleted — they are archived (isArchived: true)
• Transactions referencing an archived account remain consistent
• GetAccounts supports an AccountFilter (.active, .archived, .all)

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Implemented Features (Phase 1 — Local)

• Transaction list with swipe actions (delete, edit)
• Add and edit transaction with multi-account split
• Transaction detail view
• Account list grouped by institution
• Add and edit account
• Account archiving
• Inline institution creation from the account form
• Full local persistence via SwiftData
• SwiftUI previews with seeded data (PreviewHelpers, PreviewData)
• Typed error handling per domain (TransactionError, AccountError, InstitutionError)

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Upcoming Features (Phase 2 — Remote)

• Firebase save (offline-first) + SyncManager with timestamp-based sync
• Firebase authentication (email/password)
• Dashboard with balances and recent transactions
• Archived accounts view with unarchive support
• iPad layout support
• Account detail view
• Date picker in TransactionFormView
• Global error handling and alerts

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Project Structure

EchoLedger/
├── App/
│   ├── EchoLedgerApp.swift
│   ├── AppDelegate.swift
│   ├── DIContainer.swift
│   ├── DIContainer+ViewModels.swift
│   └── Navigation/
│       └── AppCoordinator.swift
├── Features/
│   ├── Transaction/
│   │   ├── Domain/
│   │   │   ├── Transaction.swift
│   │   │   ├── TransactionSplit.swift
│   │   │   ├── TransactionCategory.swift
│   │   │   └── TransactionError.swift
│   │   ├── Data/
│   │   │   ├── TransactionModel.swift
│   │   │   ├── TransactionLocalSource.swift
│   │   │   └── TransactionStoring.swift
│   │   └── Presentation/
│   │       ├── TransactionListView.swift
│   │       ├── TransactionListViewModel.swift
│   │       ├── TransactionDetailView.swift
│   │       ├── TransactionFormView.swift
│   │       ├── TransactionFormViewModel.swift
│   │       └── Subviews/
│   │           ├── SplitRowView.swift
│   │           └── AccountPickerView.swift
│   ├── Account/
│   │   ├── Domain/
│   │   │   ├── Account.swift
│   │   │   ├── AccountCategory.swift
│   │   │   ├── AccountFilter.swift
│   │   │   └── AccountError.swift
│   │   ├── Data/
│   │   │   ├── AccountModel.swift
│   │   │   ├── AccountLocalSource.swift
│   │   │   └── AccountStoring.swift
│   │   └── Presentation/
│   │       ├── AccountListView.swift
│   │       ├── AccountListViewModel.swift
│   │       ├── AccountFormView.swift
│   │       ├── AccountFormViewModel.swift
│   │       └── Subviews/
│   │           └── AccountRowView.swift
│   └── Institution/
│       ├── Domain/
│       │   ├── Institution.swift
│       │   ├── InstitutionType.swift
│       │   └── InstitutionError.swift
│       ├── Data/
│       │   ├── InstitutionModel.swift
│       │   ├── InstitutionLocalSource.swift
│       │   └── InstitutionStoring.swift
│       └── Presentation/
│           └── Subviews/
│               └── AddInstitutionFormView.swift
├── Shared/
│   ├── Extensions/
│   │   ├── Double+Euro.swift
│   │   └── String+Double.swift
│   └── Preview/
│       ├── PreviewData.swift
│       └── PreviewHelpers.swift

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Getting Started

1. Clone the repository
2. Open EchoLedger.xcodeproj
3. Add your GoogleService-Info.plist (Firebase)
4. Build & Run on an iOS 18+ simulator

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Author

Julien Cotte — Academic project 2026